I wasn't offended but it seems to me that this kind of movie is telling americans that the world outside America is marked "here be dragons" (all european countries seem stuck on a post-WWII or communist regime and full of monsters waiting to prey on naive americans) and that american youth itself are a bunch of morons so ignorant about the world that they deserve the grisly ending they get. If I was an american boy I'd probably be offended by the way Hollywood depicts me (especially on teen comedies).
Anything that takes place outside of medium sized cities and towns are a setting perfect for monsters. Even without adding the horror elements, foreign cultures are by their very nature something that isn't familiar to people outside of that country. Unfamiliarity brings unease. Which sets the tone for horror. I've been to a few other countries before. In places like that, it would be easy for people outside the culture to be uncomfortable. It would be hard to tell exactly if something is
wrong or just feels that way because it's unfamiliar.
You get pretty much the same affect setting movies in isolated small towns or by having people come to the big city for the first time.
As for American youth being morons that deserve to die, well, that's just a staple of the genre and it's by no means strictly an American thing.