Differences and similarities between UWEC students and students from my university

The first thing I noticed when all the American students started moving in the halls and the campus started filling with people that the UWEC students look very young. Not even that but they all look very similar so it's hard to seperate them from each other and remembering faces. Every Freshman has a UWEC or Wisconsin sweater. They all seem to dress the same way. In my University you would see a lot of different people with different styles. So not just the looks is a big difference but also the behavior of the students. The freshman seem to be out of control when they get here. They seem to be very open and wild. In my University people seem to be more mature and reserved. They don't really want to talk to anybody or help each other because you might be some kind of competition to them. In Germany they would form little groups and it's really hard to get in these groups. Every once in a while you would find a couple of nice people in your classes who might help you but this is very rare. Here people seem to be very attentive and cooperative. However, I still couldn't figure out if this "friendliness", which is so typical for Americans, is real. I mean if they really mean what they are saying or if they are just being friendly because it's part of their culture and maybe I interpret this in a wrong way.