Waiters' minimum hourly wages have gone unchanged since 1991 in 13 states.
The federal sub-minimum wage has been $2.13 for 22 years, Scott Klinger, associate fellow at the Institute for Policy Studies, writes in a recent column.
The average server earned $20,710 last year, Klinger writes, citing the Bureau of Labor Statistics.
While only 13 states use the $2.13 sub-minimum wage, there is still a discrepancy between servers' salaries and the minimum wage in most states.
Only seven states pay servers the non-tipped hourly minimum wage, according to Bloomberg.
Waiters' salaries are supposed to be supplemented by tips from customers.
Klinger notes that there is momentum in Congress to raise the sub-minimum wage to $7.07 an hour — just below the current federal minimum wage.
A major restaurant chain spoke out against Klinger's piece.
Samir Gupte, a senior vice president of culture for Darden Restaurants, the parent company of Olive Garden, Red Lobster, and Longhorn Steakhouse, wrote an open letter refuting Klinger's argument.
"Across all eight of our restaurant concepts, the average income for hourly employees ranges from $13 to $21 per hour," Gupte said in the letter. "On top of that, many of our employees, including servers, bartenders and certain culinary positions, make even more. The hourly income of our bussers, which is often an entry-level job, is more than $11 an hour. That is well above the federal minimum wage of $7.25."
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