My no.1 pet peeve in the gym is people who throw the weights down, 'throw' mind you, not only drop.
I currently go to both true fitness as well as gorgeous first, due to location and convenience. at least in true fitness, they have signs that say not to drop the weights. In gorgeous first, every single time I go, there are some hard ass that throw their weights down. very often (read always) they are light weights. sometimes I wonder if they are not afraid of people actually laughing out loud when they look at the poundage.
I find it very distracting when you are trying to squeeze the last rep in. for f***s sake!!! if you can't control it properly, you are overestimating your weight by a mile!!!!