I have. I went to a Chinese buffet in Raleigh, North Carolina, with my family. We finished eating, went to the cashier and paid, then we left.
As we were getting into our car the 'waiter' who had sloshed lemonade into out glasses ran up loudly complaining that we hadn't left him a tip. Why such people should be tipped is beyond me.
Anyway, I further insulted him by handing him a single dollar bill, with a smile.
Because that person is paid $2.50/hr for their work.
If you don't want to tip, you should boycott the restaurant until they implement a fair wage policy.
This is an illegal wage according to federal minimum wage laws. I can't imagine the GP commenter should be responsible for labor law violations beyond reporting it to the relevant local agency. Many states go even farther, requiring the same minimum wage (excluding tips) even for tipped employees, but the federal law already requires minimum wage including tips.
Unlike boycott this way customers are given ample chance to behave even if they are not local and visiting first time.