...not tipping a server is essentially theft.
No. It's not. Not tipping a server either means they gave shit service, or you can't afford to leave one.
If you can afford to eat out, you can afford to give a tip.
Let's say you have 20 bucks, and you're getting paid the following day, but you want to go out to eat, and your bill comes out to 17.50 plus tax? Your bill comes out to be 19-something, and pocket change for a tip.
Anyway, the entire point is that the restaurant paying below minimum wage isn't the customer's problem. If they want to leave a tip for that reason, then they will leave one. If not, then it's not "theft" or wrong in any way. Like I said, a tip is a reward, and most of the time, the customer will leave one, but the waiters have no business getting upset that someone dodged a tip, especially if they didn't get a tip-worthy service.