ALISON STEWART:

The federal minimum wage is 7.25 an hour. But in 43 states employers are allowed to pay tipped workers less — some as little as $2.13 an hour, a federal wage which has not increased in 25 years.

The rationale is that customer tips are supposed to make up the difference between 2.13 an hour and the minimum wage. And if the tipped employee doesn't receive the minimum wage through tips, employers are required to pay the difference. In the industry it is called "topping up."

In seven states, including Minnesota, "topping up" is not an issue because those states require employers to pay tipped workers the full minimum wage. Tips are considered additional income.