Tara Zoumer thought she had found her dream job when she was hired at WeWork, a $16 billion start-up that rents office space to young entrepreneurs. The walls were adorned with Pop Art. Neon light fixtures encouraged employees to “Hustle harder,” and there was beer on tap.

“It was like walking onto a set of a movie,” Ms. Zoumer said.

But shortly after she became an associate community manager in WeWork’s office in Berkeley, Calif., reality set in. Ms. Zoumer said she was feeling pinched because her annual salary was only $42,000, a sum that, on some weeks, left her without money to ride the subway.

She said she thought many of her duties — leading tours for prospective tenants, tidying up, answering phones and changing the kegs — were more suited to an hourly wage with a possibility for overtime.

Ms. Zoumer tried to enlist colleagues to file what she hoped would be a class-action lawsuit to fight for overtime pay. But the company had instituted a policy that could force employees to ultimately resolve disputes through arbitration instead of the courts, which essentially shut down Ms. Zoumer’s lawsuit, since arbitration bars individuals from joining in a class action.