I think it has more to do with the culture than with the campus context. It seems to me that North Americans value more politeness and independence, whereas Europeans think more in term of honesty and reliability. That's why you hear stories of French people being "rude" and Americans being "superficial" or "fake", for instance. Building strong relationships is not impossible, but it is more difficult and it takes time, and a semester can be too short. I'd imagine it can be even worse for people with even fewer common cultural ties.