There are people out there that root for the "bad guy". There are even people who root for the ultimate bad guy, the devil himself Satan. Since the emergence of Christianity calling somebody a devil worshipper was quite the acquisition. You could get somebody killed back in the day. Even now depending where you are it might not be taken lightly.
Although, for the most part in modern times worshipping Satan or the idea of Satan as an anarchist is either seen as a rebellious phase or for the truly dedicated, a religion and way of life. They could be anywhere. In the government, the police force, in your office, or maybe even in your neighborhood. Satanists just want to do their own thing. Should we allow that as a society? In our opinion, why not?