In the opposite sex's defense, it isn't all girls, and there are an unhealthy number of guys doing it too. I think it begins as an urge to look 'cool' or at the very least, remotely decent in order to impress someone; that acts like a gate way drug and before you know it, you are trying to deck yourself up like a tree at Christmas time.
Anyway, my low-expectations of this movie aside, what would truly be shocking and terrifying is if it did well. And I have that uneasy feeling in my gut that tells me it might.