Here's the thing. I'm not really for or against beer pong, because who really gives a fuck... But if you think it's stupid it's not really that hard to just... Not play.
What really pisses me off are people that play tournaments at bars, then when you're in your own backyard they're telling you that you have to throw behind your back, twist your dogs left ear 45 degrees and spin around 20 times before you throw because your hand crossed the "line"....
STFU with that shit. That's the only time I think it's stupid. Otherwise it's basically just like any other drinking game, really. What makes a flip-cup or quarters so much better than any other game?