I have a guy friend who can detail for you just about every plot line from any Scooby Doo episode (which isn't that hard really: van breaks down in front of spooky mansion ... Shaggy and Scooby lean on a bookcase that spins them into a secret room ...). Most of the guys I know can extract an appropriate quote from the Simpsons for any situation that is humanly possible to find yourself in. I lament for them all of those brain cells used up on such useless information - boys could be rocket scientists on the memory they use for the ERA stats of the 1988 San Francisco Giants alone.While most times their quirky little factoids get a laugh out of us girls, sometimes it's just annoying because you don't get the reference. And then sometimes you just don't care about what order the tracks were recorded for some unreleased Dave Matthews CD.
But here's why I think they commit pounds of trivial knowledge to their brains: status.
The more useless information a boy has, the more prestige he has with other guy friends. Imagine the triumph it would to quote a movie like Office Space and none of your friends get the reference. He would then get to scold his friends for not having seen the movie, and he, having seen the movie, is the better man. He knows more stuff. He is higher in the imaginary ranks that boys have among themselves.
So having spongy brains that soak up movie credits and box office grosses is just another way for guys to validate their worth in a society that no longer needs them to kill mastodons and make fire.