They often act in bigotry, fighting those who say negatively about them. Also while other religions are created by people with epiphanies or someone who demonstrates divine powers etc., Scientology was created by L Ron Hubber. This wouldn't be too much of a problem except that Hubber was a science-fiction writer and much of the stuff Scientologists worship is sci-fi-ish. i.e. To most it seems more like a cult than an actual religion.