Everyone, even administrators have the right to party with anyone they like after school hours. But, when one administrator chooses one group to party and go on vacations with, there is something not right going on. It is especially smelly when that special group always ends up with the best classes and the choicest programs.
The two tier system has been around as long as time, but it was a secret society. Membership only events were kept quiet. Now it is obvious to all who is part of the "in" crowd and who is not. It might not be against school rules and it is not a contract violation, but it's not right and makes for quite a few unhappy campers.