I assume amusing adults is why they do this stuff because it makes no earthly sense to do it for any other reason.  Crazy lil monkeys*.

*I used “monkeys” as a term of endearment as a show of support for the Jillian chick on Biggest Loser.  A buncha dumbshit assholes got all offended she called the contestants monkeys on her Twitshit page or something.