Actually, a lot of socializing and bonding happens in the girls community bath and shower room - getting ready to go out on weekends, helping each other color/style hair, there is a good amount of chatting and banter. It was like that at my dorm, anyway, although I did have a single room (we all did in our building.)
We were told on a recent college dorm tour that, although freshmen could request a 2 BR suite (4 students altogether) with a shared bathroom and living room inside the suite, that it was recommended to freshmen that they get the traditional double room and use the communal bathrooms. This is because the kids in the suites tend to isolate themselves from the rest of the floor, whether they mean to, or not. No need to hang out in the common floor lounge, if one has a nice comfy living room space with only 3 other people… And like I said, I know there is a lot of socializing in the common bathrooms. The traditional double room opening onto the hall leads to socializing among hall mates as well.
My D has always had her own bedroom, but I’m insisting she have a roommate in a traditional room her first year. I think it’s a great learning experience, especially for only kids, and my dorm mates ended up being my closest friends, not necessarily my class mates or fellow members of clubs.