I have a couple of pet peeves when it comes to restaurant dining. I can tolerate less-than-ideal service at a low-end or moderately priced restaurant, but when I'm paying good money for a meal, I expect well-trained servers.
My biggest pet peeve is that my drink glass should never be empty. I would prefer that my glass be refilled before it gets to the point of being empty. Is it ever acceptable to explain that to the waitstaff at the beginning of a meal?