Even if workers don't see $15 an hour anytime soon, some say that as a result of their organizing, they're logging other important workplace victories.
Caldwell and other workers tell stories about making collective complaints or staging actions to protest long-standing issues including verbal abuse by managers, unpaid wages, broken equipment, and unpredictable scheduling. They say that in some cases, their employers have listened.
"There was no respect on the job here," Caldwell says of the Wendy's where she works. "Now that we're standing up for each other, that has really started to change. We may not have a union yet, but we're out here acting like we do."
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As Caldwell's colleague Glenna Trammel puts it, "When it's just one person complaining, they don't pay any attention, they make you feel like a second class citizen. But when it's all of us, they do."
Trammel, 60, tells a story about a paycheck that she didn't receive. For a month, she said, she asked for the check, but her managers didn't produce it. With no money in the bank, she had to borrow several hundred dollars from a relative for rent and bus fare. When she ran out of money, and goodwill from her relative, Trammel talked to Caldwell and another of their coworkers who'd been part of previous fast-food strikes. "They wrote a petition to the manager and read it out loud," Trammell said. "Two days later I had my check and [the franchise company] sent me a formal apology letter."
In response to questions about the organizing, a Wendy's spokesperson said, "We cannot speak to the situation in Kansas City, as we do not operate restaurants in that market." Instead, the stores are operated by a franchise company, which did not respond to NBC's request for comment.
Workers in other stores are seeing changes, too. Employees in Kansas City Popeye's restaurants recently received a 50 cent raise and a free meal during every shift. Workers say the changes came after they made written demands to the company.
At a Burger King in Kansas City, workers complained about old uniforms, broken equipment and sometimes being expected to attend required training while off the clock. Some also claimed that immigrant workers were regularly treated with disrespect by their bosses.
Susana De La Cruz, 26, has worked at the Burger King for five years, since she immigrated to the U.S. from Mexico. She says that one of the managers would verbally harass her. "I asked for help once because it was so busy," said De La Cruz in Spanish, about an incident earlier this year. One of the store managers "told me not to complain and said 'if you don't like working at Burger King you should just leave and go back to Mexico.'"