I went to the dark side the other day, a dangerous place that’s helping to ruin our city. The type of place that could soon be banned. I had lunch at an employee cafeteria.

A friend who works at a big tech company in Mid-Market and I had been saying we should get lunch for ages. But in the daily whirl of our busy lives, we never actually scheduled it.

Until, that is, two San Francisco supervisors — Ahsha Safaí and Aaron Peskin — proposed banning employee cafeterias in all future San Francisco development.

Suddenly, employee cafeterias were a hot topic, and my curiosity was piqued.

Would these facilities that nobody previously ever thought twice about join the list of items and activities San Francisco has banned — evils such as free toys in Happy Meals, fur sales, plastic straws, flavored tobacco and sitting on the sidewalk? And foam pool toys, phone books and packing peanuts? And chocolate milk in schools, street chess and walking more than eight dogs at a time?

What was so bad about these employee cafeterias to place them on that dastardly list? I was determined to find out.

Sadly, I can’t tell you which tech company I visited because I didn’t prearrange it with the company’s bountiful media team. I just went as a regular old friend, but was made, like all visitors, to sign a nondisclosure agreement because you never know what friends having lunch might be up to.

Inside, it was like nothing I’d ever seen. We occasionally get doughnuts at The Chronicle, and we get pizza on election night. But this was totally different.

There were three identical buffet lines to accommodate the hordes, each one offering a variety of Chinese food options. Most days are themed, burgers and sushi being among the most popular.

There was a salad bar, lots of desserts and “spa water” in flavors including mint blackberry ginger and cucumber lemon. Both, the labels noted, were vegan, which was good because I don’t like meat or milk in my spa water. You could also add chunks of pineapple or watermelon if the premade flavor concoctions weren’t complicated enough.

There was also a coffee bar and a smoothie bar, the latter of which had trays of ready-to-go smoothies, including one with kale, spinach, avocado, mango and coconut water. They were also, the label helpfully noted, vegan.

The idea of banning future versions of this lovely, yummy oasis in Mid-Market came up because tech employees supposedly cloister themselves inside and don’t patronize neighborhood restaurants. I would cloister myself inside too if I had access to all that free, delicious food.

“We intended to spark a conversation,” Safaí explained. “I’m a city planner by trade, and I think about what makes for a healthy city. You start with some of the foundational principles, and one of them is small businesses are the backbone of a city.”

True. That’s why I recently wrote about small business owners feeling overwhelmed by the myriad quality-of-life issues just outside their storefronts, and often encroaching inside, such as dirty needles, drug addiction and severe untreated mental illness. City Hall hasn’t done much to help those businesses, but then tackling major societal crises is harder than coming up with random bans.

I asked whether Safaí had other ideas for helping small businesses, including restaurants in Mid-Market, such as addressing the neighborhood’s major quality-of-life issues. Maybe that would improve business?

He said getting workers out of their offices to buy food would increase “eyes on the street,” and that would improve the conditions on our sidewalks. Yes, because neighborhoods with a lot of foot traffic such as Union Square have none of these problems.

Peskin, who downplayed his role in this big brouhaha as being just Safaí’s “wingman,” said, “Getting folks out of those self-enclosed buildings and onto the streets will be remarkably helpful for Mid-Market.”

But if banning new employee cafeterias would be so beneficial to our city, why stop there? Why not abolish all the ones that exist already? The company I visited for lunch also offers acupuncture, chiropractic services, massages, a weight room and a yoga studio. Should those be banned so workers must patronize local yoga studios and gyms?

At The Chronicle, many workers bring their lunch. Should that be banned so we have to go outside and buy food? Should office kitchens be banned so we can’t reheat leftovers? Should catering — what many tech companies without full cafeterias offer instead — be banned?

A new Change.org petition satirically takes it even further in ban-happy San Francisco. It calls for a prohibition on kitchens in supervisors’ homes so they, too, are forced to go outside and mix with the masses when they eat.

Safaí laughed good-naturedly at that idea and said that with two little kids, he and his wife buy plenty of burgers and chicken fingers from neighborhood restaurants.

Jennifer Stojkovic, executive director of SF.citi, which advocates for tech companies at City Hall, said employee cafeterias offer “high-quality, high-wage jobs in the food-service sector.” She said one member company that is hoping to move to new office space, and thus would be prohibited from offering a cafeteria, would have to lay off 100 kitchen staff if the ban is approved by the Board of Supervisors.

Yes, tech companies and their lavish perks can be kind of annoying to the rest of us. It is a little obnoxious that tech workers are drinking free spa water in an office above Market Street as people sit begging for change down below. But would banning cafeterias do anything about that? No.

So how about reopening the community benefits agreements City Hall struck with the companies receiving the Mid-Market tax break and encouraging each one to close its cafeteria a couple of days a month?

Stagger them so a different batch of tech workers is out and about on Market Street each day. Create a public awareness campaign encouraging tech workers to get outside their buildings and patronize other businesses. Organize pub crawls or other events that would lure people outside.

But mostly, work on what matters. Like building housing much more quickly, including affordable housing, so everybody from a line cook to a tech worker can live here. Like cleaning our sidewalks so more people want to walk around our neighborhoods. Like moving homeless people into shelters and getting rampant injection drug use off our streets.

You know, the stuff San Franciscans of all employment types actually care about and that will make our city better for everybody.

San Francisco Chronicle columnist Heather Knight appears Sundays and Tuesdays. Email: hknight@sfchronicle.com Twitter: @hknightsf