They proved that hipsters are game for anything — as long as you make the hangout cool enough.

Starting in Manhattan in the late 1990s, the bowling-company Bowlmor, with a new kingpin at its helm, began taking over seedy rundown alleys and turning them into trendy hot spots, wooing 20- and 30-somethings with the promise of quirky booze-filled fun.

No more middle-aged bowlers with beer guts and tacky shirts.

Beautiful people now regularly fill Bowlmor’s alleys, including even First Lady Melania Trump, who took her son Barron and stepdaughter Tiffany to the lanes at Chelsea Piers this month with 30 Secret Service agents in tow.

But the push to transform the bowling joints from haggard to hip had an extremely ugly side, former workers told The Post.

In its greedy bid to make strikes and spares cool again, the largest recreational bowling company in the world threw out its aging “average Joe” staff for “trendy, attractive” new hires — even hosting “beauty contests” on Skype to hire the best looking “hippest” candidates, ex-employees say.

Bowlmor AMF — with locations across the country, including in Times Square and the Chelsea Piers site — is now facing more than 50 discrimination complaints filed with the federal Equal Employment Opportunity Commission. Ten of the plaintiffs are from New York, according to their lawyer, Daniel Dowe.

“These people can’t get away with what they’ve done,’’ insisted former Bowlmor manager Miguel Martinez, 59, referring to company officials.

“You can’t treat people this way,’’ he said. “We’re human beings, we’re not cattle.”

Bowlmor has a long rich history in New York City.

It began operating in Manhattan in 1938, opening an alley on University Place in Greenwich Village.

But while the spot lured top bowlers for decades, by the early 1990s, it was languishing — badly.

Enter Tom Shannon. In 1994, the Darden Business School grad visited the dilapidated alley for a birthday party. Looking past the smoke-stained walls and shady neighborhood regulars, he saw dollar signs on every scratched-up red and white pin.

Shannon, 51, bought the alley in 1997 for $2 million with the help of investors and started transforming its greasy interior into a gleaming nighttime gathering spot for the rich and famous.

He eventually went national with his business plan, buying up tired alleys and breathing lucrative new life into them by installing massive flat-screen TVs, glow-in-the-dark lanes and upscale design elements.

In 2010, Bowlmor Times Square opened in the former New York Times newsroom.

When competitor AMF Bowling Worldwide filed for bankruptcy in 2012, Shannon saw another business opportunity.

In July 2013, Bowlmor Lanes took over AMF and began transforming many of their shabby bowling centers much the same way it had with its New York spots, wooing millennials with night bowling, DJs and eclectic food and cocktail menus.

But there were casualties along the way.

Between 2013 and 2015, the company fired 287 managers from its 351 bowling centers, gutting the business from the inside out.

Higher-ups replaced the outgoing managers with younger, more attractive talent who were given “comparable, if not higher” salaries, ex-workers say.

“We started terminating people for no reason at all,” said Kelly Shannon, a former HR manager who oversaw new managerial hires in the northeast region and is now an EEOC plaintiff.

The ex-manager, no relation to Tom Shannon, said Bowlmor asked her to start creating profiles for the managers in her region, which included a picture and a short biography.

Then company execs, including Tom Shannon, started visiting those centers, she said.

“If [higher-ups] went to a center and didn’t like the way the general manager looked . . . whether it be age or appearance, they came up with some way to terminate them,’’ Kelly Shannon told The Post.

“We were told a lot to give the excuse that ‘we were going in a different direction.’ ”

The 35-year-old former exec recalled a conference call she had with a regional vice president in Chicago who had just done a site visit with a general manager there.

“[The veep] made the comment that [the manager] looked like he weighed 435 pounds,” Kelly Shannon said. “Shortly after, we terminated him.”

She said there was no documentation of bad performances by those who were booted — “just a visit from a higher up a few weeks before the firing.”

She said Tom Shannon started requesting Skype interviews with potential candidates before they were hired. But he wouldn’t ask standard interview questions and kept the sessions extremely short, Kelly Shannon said.

“It was a 2-minute quick look of a physical appearance of someone. … there wasn’t any depth to the interviews. . . . He wanted to Skype interview to see if this person’s young or attractive,” she said.

The Skype interviews were essentially “beauty contests,” Shannon said.

Kelly Shannon said she was eventually fired because of the pushback she began giving her bosses. She said the company claims it fired her over a DUI charge she received and didn’t tell them about promptly enough. She denies the claim.

Bowlmor AMF told The Post in a statement that the company “does not discriminate on the basis of age or in any other fashion.”

“We are aware of some untimely claims made against the company based on individual personnel actions that were taken several years ago. None are meritorious, and in some cases the company suffered money and property loss.

“The company will vigorously defend any claims and believes that it will prevail,” it said.

Miguel Martinez was one of the company’s targets.

The married dad got his first job in bowling at 17 in The Bronx and had a passion for the business for the next 40 years of his life, working in centers across the tri-state.

He was hired as a general manager at the Rip Van Winkle Lanes in Norwalk, Conn., an AMF center, and after almost a decade of working there, he was fired “out of nowhere,” he told The Post.

“I’m 100 percent sure it was because of my appearance,” said Martinez, who weighed about 450 pounds when he was fired in August 2013 and has since filed a complaint with the EEOC.

“I put two and two together. … It’s because I’m overweight, I’m older, and I don’t fit the Bowlmor vision of what they’re looking for.’’

Back at the corporate office, the CEO had just gotten back from visiting Martinez’s center and wasn’t happy with what he saw, according to Kelly Shannon.

“Tom Shannon visited his center and felt like Miguel wasn’t healthy. . . . They made a comment about him being overweight. . . . They said, ‘He obviously can’t walk the concourse’ and they wanted an upbeat, young person that can be up and down the concourse,” Kelly Shannon said.

She said she was told to start “working on some sort of documentation on Miguel’’ that “had teeth” but that she knew they had “no reason” to fire him.

Martinez told The Post that he treated the center as if it were his. He stopped in on weekends when he was off just to make sure everything was in order.

When his 11-year-old son died from complications related to cerebral palsy, he was at the center two days after he passed.

When he had a knee-replacement surgery, he came back in a month earlier than he was supposed to.

Martinez said he had one of the “highest-customer ratings and one of the highest-employee ratings in the region” and got a nearly perfect score during a company audit a few weeks before he was fired.

“I said to myself . . . ‘Wow, am I crazy? I’ve done nothing wrong, I’ve never been written up, ever year that I’ve been there I’ve been one of the most popular candidates there,’ ” Martinez said.

He remembered his boss “tearing up” during his firing because he just “couldn’t answer why.

“Nobody could answer me why,” Martinez lamented.

He said he’ll never forget that “long drive home” back to his house in upstate Orange County, where he wracked his brain trying to figure out what he was going to tell his family.

Martinez said he declared bankruptcy and fell into a deep depression after he was fired and gained nearly 50 pounds, bringing his weight up to almost 500 pounds.

Former Bowlmor manager Adam Csernay, 54, believes that he was fired because of his refusal to terminate an older employee.

Csernay, who has an EEOC complaint pending, worked as an assistant general manager at the Chelsea Piers bowling alley for three years and was promoted to general manager at the AMF 34thAvenue Lanes, now Bowlero Queens, in 2012.

He had escaped communism and came to New York from Hungary as a political refugee in 1988 and said he enjoyed working in the bowling industry — until Bowlmor came in.

“Without ever any kind of disciplinary notice or anything like that, I was just let go,” Csernay told The Post.

He recalled a day in late 2013, shortly after Bowlmor took over, when the regional vice president, Justin Hake and the chief operations officer, Joshua Silverstein, came to visit his center.

“We were standing by the snack bar talking about what we were going to do to renovate the center, and Justin Hake says to me, ‘You know, there is something wrong with this picture,’” Csernay recalled.

He said he replied, “What do you mean, what picture?”

Hake, who was district manager at the time, allegedly pointed to an older gentleman who ran the front desk.

“He’s too old to be here,” Hake said, according to Csernay.

Csernay told the higher-up he didn’t understand.

“Why would I fire him? He’s an older gentleman, yes, but knows every league bowler in New York City,’’ Csernay said.

But Hake said, “He just has to go. … I don’t want to see him at the front desk, he’s too old,” Csernay said.

Then Hake and Silverstein broke into laughter, the former manager said.

Csernay said there was a “culture that older people were not [good for business].”

He was finally let go in the spring of 2014.

“That was a little bit of a low blow… I was older, they were looking for somebody younger for that center, it became more of a hip place, it was more of a night club alley as opposed to a regular bowling alley,” Csernay said.

“I would work 120 hours a week, I put my heart into this thing,’’ he said. “In the end, it didn’t matter.”