A Denny's waitress delivers breakfast to customers in Emeryville, Calif. The tipped minimum wage has been stuck at $2.13 since 1991. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images

Fast-food workers march toward the Smithsonian's National Air and Space Museum in Washington, D.C., on Thursday. Similar rallies occurred in about 100 cities across the U.S. Morgan Walker/NPR hide caption

itoggle caption Morgan Walker/NPR

McDonald's USA President Jeff Stratton responds to an employee who burst into an event. YouTube screengrab hide caption

itoggle caption YouTube screengrab

A group that advocates on behalf of food service workers has created an app that helps diners find restaurants that pay their workers livable wages and offer room for advancement. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Culinary student Nadya Dunkley cooks chicken at Colors Restaurant in New York. The restaurant scored highly in a new guide that rates restaurants based on the way they treat employees. Kathy Willens/AP hide caption

itoggle caption Kathy Willens/AP