Paint it how you will, but this is no different than mocking someones race. It is an act clearly meant to offend a single group of people.
Btw, I really am not terribly offended by it, but I am tired of people excusing such actions with a "aw..they were just drunk", or "kids will be kids, you know". Call it what it is. Bigoted. And Utah has better people than that from what I've seen. (I'm not from Utah, but I did live there once.)