Interesting observation. Anything that creates an emotional bond & takes down walls is going to build long lasting relationships among people. So partying is one of them. Especially if you are at a top school where most of your peers will end up at important places. You want those strong relationships since we all know business is people.

Building a network that's reliable is far more than someone you met at a meetup and added them to your LinkedIn. It starts either at school or through some social functions where one can connect on a deeper level than just a title.

Maybe this is why it's so much harder to form meaningful bonds later in life.

Also makes a good case for formal education and a school that has good signaling ;-)