[ItalianStereotype]

There is absolutely no reason not to tip. If you're really such a douchebag, don't expect anything good to come of your time in a restaurant. Most of the time, we can tell if you're going to leave us a shitty tip within the first few minutes of your time there and I personally like to earn every red cent of that $1 you were planning on leaving me. I'll make sure your glass stays empty, you don't get more bread, your food goes out cold, whatever it takes to piss you off and get you out of my section so that someone who isn't so worthless can have a seat.

If you're a minority, it probably won't matter either way.