The left is only allowed to be pro-hedonism for hedonistic activities that are exclusively performed by their in-group. It's why you can smoke a joint pretty much wherever you want in Seattle and no one cares, but if you smoke a cigarette all of a sudden people get very interested in whether or not you are the proper legal distance away from buildings and public areas.

According to Curtis Yarvin it's actual literal puritanism that's slowly evolved into what we see now. He did back up the argument but I don't know enough american history to know if he's full of it, but if it walks like a duck-