Bingo. If I'm not mistaken, it has as much to do with perceived social good as much as the size of the community supporting it. Established religions often have considerable resources at their disposal which they can put to use defending the legal rights of their adherents (or establish, depending on the point in the timeline). Small, siloed conspiracy communities don't have that same centralized organization to coordinate efforts, let alone the financial means to challenge a country's legal system in the larger sense.