Actually, it's quite a few doing nasty things.
Outside of the rampant stupidity there are videos of anti-semitism, communist party members, and more. You could find them easily yourself if you cared to. Go look. And it isn't the same people every time, either.
When I think of the hay that got made about one or two signs at Tea Party rallies, it's amazing how much the media is covering the unwashed asses of the current protestors. And yes, if a Tea Party member had crapped on a car, it would have been headlines for weeks. I had to go to frigging England for that story.