confusion

We had a party this weekend, and I had vowed not to drink. ( It really does suck to be sober; I realized that I don’t actually enjoy parties where I don’t drink.  What the hell is wrong with me?  So after the party I was walking a friend home and she gets a call from this dude, who asks her to come on a drive with her.  This dude was drunk as hell, and this girl actually sits in the car with him.  I tried to stop her, but oh well; I guess people have their own compulsions.  Why are people so dumb? Why do they have to do the stupidest things all the time? Why are people hardwired to do dumb stuff?  I just don’t get it.