Why do women laugh when men get hurt in the balls?
Men laugh as well. It's a type of comedy. Crude, physical, slapstick, etc. South Park even had an episode involving it with Butters repeatedly shooting guys in the dick and Cartman yelling at him for it. Personally for me the darker and more twisted the comedy is the more I find it hilarious. Sometimes I even laugh during horror movies at scenes that are not meant to be funny. This one movie I saw had the villain find a woman who was hiding because he heard her cell ring. When he found her he grabbed her and shoved the phone down her throat. Fantastic. Laughed so hard. Love this sort of comedy.