ya nick it's totally a north american thing.
there's a completely different culture when it comes to being at a sporting event here and in Europe. and a big change like that will probably never happen. It will never happen on its own and i can't see the teams or the leagues encouraging it. North American sports are marketed as family friendly events.
The only reason why you see it with MLS clubs now here is because they're doing everything they can to recreate a european atmosphere and their doing this as a concious decision to carve out a niche. which is cool because i lean towards that kind of support.