I had to draw the line at sex toys.

A Facebook invitation titled "Girls Night In!!" promised games, wine, and "an evening of fabulous fun" at a friend's house. I read on for the rest: Would I be interested in tips and tricks to improve my relationship? And what about the chance to learn about a brand new line of products — no pressure! — from an exciting company called Pure Romance?

By then, I'd become accustomed to these kinds of parties, where friends who work for multilevel marketing companies try to sell me their wares. I'd watched cooking demos. I'd sniffed dozens of candles and essential oils. I'd flipped through before-and-after pictures of bellies tightened though health shakes, exercise videos, and body wraps. I'd listened and nodded when friends spouted sales pitches for their favorite products.

A few times I even ordered something. My little purchases — a $17 cutting board, a $30 necklace — barely represent a drop of the $7.5 billion spent at home parties each year, according to estimates from the Direct Selling Association.

I've come to recognize MLM as another outlet for female ambition, for "leaning in" and "having it all"

When the Pure Romance invite came, I imagined myself grazing on store-bought cookies and trying to make small talk while an acquaintance from church vied for her commission on lube and vibrators. The scenario seemed so absurd that it caused me to question the whole industry. Suddenly, the pitches filling my Facebook feed and the parties stealing away Saturdays didn't feel like an annoyance to endure but a mystery to unpack: What's really happening here?

Multilevel marketing (MLM), this model of friends selling to friends on behalf of a company, hadn't just taken over my networks; it was everywhere. About one in seven US households include someone involved in direct sales, and participation skews female — 92 percent of in-home sales parties are thrown by women, the national association reports.

Thirty-One Gifts (personalized bags), Team Beachbody (fitness products), It Works! (weight loss wraps), and Scentsy (candles) all entered the industry within the past decade or so, and thanks to mostly female customers, each now brings in around a half-billion dollars a year. (Side note: A company whose name includes the words "it works" and an exclamation point? How reassuring.)

MLM is not only growing financially but spreading geographically. Though traditionally more popular in the Midwest and South, home parties are turning up in Northeast cities, the New York Times noted last year, with sellers packing friends into small apartments to sell jewelry, beauty products, and, yes, sex toys.

It's a complicated trend. It's not always easy to parse the motivations of the sellers, who rely on their networks for income, or of the companies, which often stand to profit at their distributors' expense. And as uncomfortable as it can make me, I've come to recognize MLM as another outlet for female ambition, for "leaning in" and "having it all." Its surging popularity reflects, and attempts to address, our current social tensions over women and work.

Why women are drawn to multilevel marketing, as sellers and buyers

Women are primed for MLM as both buyers and sellers. After I got married and moved to suburban Tennessee in my mid-20s, I discovered that anywhere women gathered —yoga classes, PTA meetings, Bible studies, mom groups, Bunco leagues, book clubs — there was a party invite or sales pitch lurking.

Eager to make connections with people in a new place, I was content to at least hear them out. Psychologists would probably say that some of this impulse was due to my gender; women who want to protect relationships often avoid the disruption of saying no. "It's risky because [MLM] promises women time with their friends, and downplays the sales aspect," one sociologist told the New York Times. "But of course, ultimately the goal is to sell products."

In my new community, at-home moms hosted parties as a way to start working again, and working women added MLM as a side hustle. Amped up by company training and fellow sellers, these women were motivated to do their thing — to work on their own schedule and scale, to establish their own goals and milestones. They were so passionate about their products and companies that they wanted to recruit me to sell too.

This approach has been popular since Brownie Wise invited fellow '50s housewives to demonstrate Earl Tupper's line of plastic containers at one of her "patio parties." Just a few years later, in 1954, Kiplinger's Personal Finance wrote that 20 million American women a year attended "sales parties in the home."

Nearly that many sell MLM today. Their gatherings go by many names: ladies' nights, parties, coffee dates, receptions, and brunches. The internet adds a dimension that Wise never had, nor our mothers who sold Mary Kay and Avon. Today's MLM salespeople aren't limited to the ladies they see around the neighborhood. Through online parties, they present their entire social network with their product testimony and the opportunity to buy.

A sorority sister looped me into a Facebook group for a lash-lengthening mascara by Younique, the first company built almost exclusively around these online parties. For two weeks, she shared before-and-after pictures of her eye makeup, her lashes shooting out like tiny black pipe cleaners, and reminded us that for $30 we could get the same results.

Only a tiny percentage of sellers make money from multilevel marketing

To get started, MLM sellers usually pay $100 to $250 upfront for a starter kit of products to display and demonstrate. Once customers place orders, they earn commission in money, free products, or both. When my best friend looked up a nail wrap company she discovered through a friend pitching on Facebook, she was shocked to realize, "She sells Jamberrys to earn more Jamberrys." The bonuses her friend was working toward came in the form of retail credit; after selling dozens of nail wraps, she'd make enough to get six or seven sets for herself.

The big money comes from recruiting additional sellers and earning a percentage on their sales too. The more friends they can convince to join their sales teams, the more they can compound their own earnings ... and company profit. But here's the catch: The vast majority of the millions of women sending out Facebook invites and setting up party displays on coffee tables don't develop the robust, sustained "downlines" necessary to make real profit.

Financial disclosure statements reveal that across companies, women who make bank from MLM are the 1 percent ... or the 0.1 percent. For example, a few dozen Thirty-One Gifts consultants do get paid six-figure sums. But it's no get-rich-quick scheme — they have been building their businesses for five to 10 years before reaching the top tiers, where they have higher commissions, bigger bonuses, and more consultants under them to mentor.

Most MLM reps remain at the lowest level of the company. They may bring in a few hundred to a thousand dollars a year, if that. At Thirty-One, 92 percent of the 130,000 consultants make $500 a year on average. At Young Living, so many distributors sign up just for the personal discount on essential oils that nine out of 10 average just $12 a year.

Even a relatively small check each month can look and feel like income — enough to cover a few bonus purchases, a pedicure, or a weekend vacation. In reality, though, it rarely outweighs the time and costs of doing business. Promotional materials, training resources, party supplies, and taxes add up. Some companies, like Team Beachbody, require sellers to pay a monthly fee and continue to buy the products.

The awkward social dynamics of MLM

The social cost can be huge, too. When I began asking my friends directly about MLM, they were relieved to finally open up about something so pervasive yet rarely discussed. I heard stories from people who cut off relationships due to the sales pressure. Many admitted to blocking Facebook friends whose updates constantly centered on their company and the new sales levels they reached. Several stopped speaking to friends — even siblings — who continued to ask them to buy, or to get in on the "opportunity" to sell, even after they had declined.

Beyond the awkward social dynamics, I noticed a shift in identity among the sellers I knew. These smart, college-educated women began parroting the companies' lofty promotional language of purpose, empowerment, and personal development. It Works! invites sellers to "live the dream" of paying off debt and spending more time with their family through becoming a "wrapreneur." Scentsy wants you to "reach your goals" and "find joy in the journey."

These women declared that their whole lives had changed thanks to MLM. They'd found their dream jobs as small-business owners and saleswomen. Not only that, they were happier, healthier, better versions of themselves, all because of whatever beloved product they were pitching.

To me, on the outside, it looked like overcompensation. It seemed like they were selling out and settling for a job that could potentially steal away time and money without much to show for it. I thought — perhaps narrow-mindedly — that they could do better than a kit and a sales pitch.

Financial disclosure statements reveal that across companies, women who make bank from MLM are the 1 percent ... or the 0.1 percent

When I took a closer look, though, I realized there was something far more significant than products, parties, and profits going on. Multilevel marketing strikes certain women deeply. It gives them something they aren't finding elsewhere: a sense of achievement, mentorship, community, or purpose.

Some women struggle to thrive in traditional office settings, and work-life and work-family tensions are obviously major reasons for that. When workplaces lack substantial maternity leave, child care options, or flexible schedules for working moms, women from the high-achieving lawyer to the hourly worker can burn out fast. (In case you forgot, the US remains the only developed country without mandated paid leave options for parents and where moms routinely face job and pay discrimination.)

I watched a former classmate return to her marketing job a few months after having her first baby. No less than two weeks later, she announced her plans to leave the business to stay home with her daughter ... and sell skincare products from an MLM company called Rodan + Fields.

She called the switch an "exciting new journey," even though she left behind a full-time salary and benefits for 10 percent commission on a few parties and online sales a month. The chance to work from home and set your own hours has that strong an appeal.

Certain subcultures present additional barriers for working women. I'm the exceptional Army wife who gets to work full time and has been able to keep my job as a remote-based editor as we get transferred from duty station to duty station.

Few military spouses get so lucky. I've met wives who intended to become teachers, researchers, realtors, and nurses but ended up as housewives or stay-at-home moms due to military moves. The parking lot for the commissary on post is dotted with car decals advertising sellers' custom websites for Thirty-One Gifts and Scentsy.

These ventures have also taken off within religious communities. As I reported for the evangelical magazine Christianity Today, several major MLM companies — from historic Amway to Thirty-One Gifts — were founded by Christians, and they incorporate worship and Christian speakers into their corporate training.

Additionally, Jamberry, Younique, doTerra Essential Oils, and Young Living Essential Oils are all headquartered in a heavily Mormon area outside of Salt Lake City. They can provide a loophole for women whose faiths discourage them from working outside the home.

"As long as MLMs are regarded by conservative Christians as a more honorable option for women than a normal part-time or full-time job, these organizations will continue to attract women within the church at significant rates," said Jen Wilkin, a Christian author and minister who leads a women's Bible study in Dallas, in the Christianity Today article.

In the midst of military communities and church culture, I'm always navigating around MLM. We've since moved from Tennessee to Georgia, where I had to start making friends all over again. After a few weeks at a new church, a woman finally invited me to hang out. I thought I'd made a connection at last — only to end up sampling essential oils on her couch that night. I came home with a tiny bottle of cedarwood oil to rub on my feet to help me sleep.

For us friends turned clients, it's hard not to be cynical or skeptical. But perhaps some of our questions are best directed at the surrounding society, rather than just the sellers themselves. The workplace norms that put women at a disadvantage — and other practical, theological, and cultural considerations — are ultimately what force many women into MLM. They may not see another way for fulfilling (and hopefully profitable) work.

The MLM industry can be a wake-up call to communities and companies. Women are so motivated to work that they'll do it for next to nothing and will bring their friends, relatives, and neighbors into their businesses. Imagine how successful they'd be if they were given the adequate support, flexibility, and training to do it in your office.

Kate Shellnutt is a journalist covering faith, women, and pop culture. She works as an editor at Christianity Today magazine, where she wrote a cover story on the relationship between evangelicalism and multilevel marketing. Find her on Twitter @kateshellnutt.

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