Ya know what... maybe it won't go away. Just like blue jeans haven't. The one time scourge of parents and teachers everywhere are now one of the most common pieces of clothing.
I doubt that the super sagging look will catch on with the general public though. It's actually work to have to wear em like that. Most people, after a certain age anyway, are going for comfort over fashion.
Despite it's origins, it's just a fashion statement. That statement might be, "Hey look at me, I'm an idiot", but other than wearing their stupidity on their knees, it's not really hurting anything other than their reputation. And if they don't care about what people think, then I don't care to try to convince them otherwise. And making laws isn't going to do anything. It'll only make matters worse in that you're denying them self-expression and they'll find other ways to express their angst and rage. I'd rather they wear stupid clothes than destroy property or resort to violence.
I think too after they reach a certain age, it stops. Something I've noticed too though, is that a lot of youth are going for a preppier look. I was talking to a dude thats my age, and went to a rival high school. We were reflecting on our experiences, and he made the point that he's glad to see teenagers dressing preppier. When we were their age, we were wearing Dickies, Carharts, ski masks in the winter. Public buses wouldn't let us on the bus if we had the ski masks on. We looked like killers, and there were killers amongst us, although the far majority including myself were just going with the flow. Nowadays though, there's room for kids to dress preppy, and in some cases like quasi homosexuals. So maybe kids are moving away from the G-look. I guess I should thank Kanye and Jay.