"If you intervene, it's a bit assholeish and paternalistic and awkward. If you don't, you're being irresponsible by letting your drunk friends do things they might regret."
The problem here is that trying to protect people from things they *might* regret... is paternalistic. I think it's clear that paternalism should be avoided. You should probably lower the threshold a bit to "things they [almost] definitely will regret." To illustrate, it's certainly paternalistic to stop your friends from drinking, from driving, and from smoking weed. It's not paternalistic to stop them from doing all three at the same time. Point is - each activity on its own has the possibility of regrettable actions, but the chance is relatively minimal in isolation. You combine those three and yeah, there's a good chance something quite regrettable is on the near horizon, and it would be irresponsible not to do something.
So it comes down to likelihood of regret; you can't just try to stop anything they might regret.
As for the more general question, I'm not a partier at all, but I certainly deal with people who are, and I would say that both:
(a) gender relations (and specifically gender parity) show up more often in partying situations than in normal life, and
(b) the partying scene is a backwater shithole of gender relations (which is honestly one of the reasons I never got involved; quite frankly, it is extremely difficult to combine sticking to my principles on the matter and being successful at attracting most college-age females).
So yeah, your feeling on the matter isn't without merit. My advice is to go find a woman that not only agrees with those principles of yours (because many would, were they to hear them) but then actually lives them out (because of those many who would agree with them, most wouldn't live them out) and just exclusively date instead. Unless you're into polyamory that should work.