Who said horror had to be only scary? I like a movie that can pull double duty and scare me while making me laugh.
Together, horror and comedy create an enjoyable, rollercoaster-ride viewing experience. It’s excited to have a genuine scare only for it to be undercut by some silly slapstick the next second. There’s a pleasurable in the back and forth there, a kind of compare and contrast with the basic human emotions of fear and happiness. Maybe there’s also something there about how horror and comedy are very closely-related, cousins if you will. They both provoke catharsis, but in different ways.