We have a great tradition of adult Halloween parties here in the US, right up there with New Years eve for drunken wild times. Women like to dress in slutty costumes, slutty vampire, slutty nurse, slutty gypsy etc.. Men can dress as a pirate! or wear a gorilla suit, for some reason women like getting groped by someone in a gorilla suit, some sort of primal urge? You can wear a mask and behave inappropriately and people don't know who you are.
All great fun perhaps you are missing out on?