I only own 4 belts. I always wear one if I am wearing something with belt loops. I just think it looks weird without a belt!
My sister owns...oh...a million belts. Ok, not that many. She has maybe 30. She likes to wear mutiple belts. It's very interesting. And she started using suspenders as belts, too, which looks kind of neat (she's sort of into a punk-ish style of dress).