On one college trip I went on, we went to Savannah, GA, I remember they said it was ok for those of legal age to drink as long as they could get a ride back to the hotel. I wasn't 21 yet, neither were the other gals I was sharing a room with, so it wasn't any type of issue for us. However we weren't all crowded together or around Amish. That just seems inappropriate to me. It would also really suck to not be able to shower after a night of drinking and/or being around people who also haven't showered after drinking. . .Ugh!
As for going, I guess it would depend on room arrangements. If it's one big room and you wont get any sleep that doesn't sound very fun.