You are being made a sucker by state police propaganda. I know it feels good to you to believe in the BS line that this was some kind of bad frat behavior, but try to keep up. 18 other Greek orgs did not participate. No Greek orgs participated. Members of 18 Greek orgs probably did participate, maybe even more, but that's because it was a party that was open to upperclassmen and a lot of them happen to be in Greek orgs. I'll bet there were a lot of kids from Pittsburgh at this party, too, but I don't see anyone calling this out as an out of control Pittsburgh party.
The bottom line is that after shitting the bed with the helicopter, the police apparently couldn't deflect by pointing to wide-spread underage drinking, so they went with illegal wrist-band selling topped with a generalized reference to "frat" involvement, which is generally sufficient to mesmerize knee-jerk frat haters like yourself. Mission accomplished.