You just reminded me of a memory trying to fall asleep during the off-site orientation week while my cabin-mates were playing drunken games in the room/cabin next door.... ah, the first few weeks of BSchool. I am not a big partier either, esp when it comes to a large crowd of strangers.
Party culture and concerns about it are usually not a big deal even in schools such as INSEAD where they have a strong work hard/play hard culture. BSchools are diverse for a reason and you will definitely find a comfortable group/spot after just a few weeks in, esp in large programs, which all Top 10 are except Tuck, which being as remote as it is, my guess, is not a big party school (only a guess). You will have a variety of folks in your class - you will see some of the smartest people in your class drunk at night making fools of themselves and you will have party folks who want to include everyone and who will try to do everything they can to include you in a vegas trip or a get together during the first few months of bschool. Reality sets in, hours are long, and to keep partying you have to be either really really hard working or plain stupid. The married folks tend to hang together and they are pretty quiet bunch, frugal, and realistic, usually, esp if they have kids. Their party days are over

Anyway, as with every corporate culture, each school and company is unique and so is every individual. You will, however, find that despite some character flaws, all of your classmates will be pretty amazing people with long lists of accomplishments and once you get to know them, you will see past some of the temporary intoxication side effects, as they will have a lot of redeeming qualities to them....