People who yell at their dogs when they bark
I have several neighbors with dogs. It drives me nuts when the dogs are barking and their owners start yelling at them to be quiet. It doesn't work. The dogs don't listen and now I have to hear both of them. Train your damn animal properly! Don't just stand on your porch and holler at them, because obviously it either has no idea what they want or it doesn't care. In fact, unless the owner has specifically trained it to understand what "be quiet" or "shut up" means, which I doubt, they're probably just making it worse because now the dog thinks the owner is barking with them.