Over time the businesses noticed their servers were making a lot of money in tips so they reduced their pay to minimum wage. The difference between that and what you should have been paid was made up by tipping.
http://www.dol.gov/whd/state/tipped.htm
I stand corrected. I have not worked in food service for over 30 years so I can only presume the rules have changed, and not for the better. My current experience is from the other side of the table.
You make $2.13 an hour and have to split your tips with Paco the busboy, Juan the sous chef, and Luis the dishwasher, as well as the bitch barmaid that that didn’t restock the bar after her shift because she doesn’t have to because she is banging the shift manager.
That whole lifestyle... makes me glad I eat at home.