EDIT: I do have a different expectation for parties, but understand that parties have a spectrum, from people going to a party to drink/smoke/bump what have you to reach a point of near senselessness on one end of the spectrum, to perhaps a gathering of people in the same industry who are trying to "network" at the other. My expectation for informal parties is in the middle of this where people may drink but where it isn't their expectation that they will get drunk, and the discussions will be more intimate and not business related.