Scary clown masks are most definitely not for childrens parties. There are now so many cases of coulrophobia (fear of clowns) which might explain why so many people like to wear evil clown masks, to scare their fellow party goers at Halloween. Why are so many people afraid of clowns? We have a plethora of Halloween clown masks, from the little bit frightening to the absolutely terrifying. Dress as Pennywise from IT in an evil clown mask and scare the bejesus out of your friends.