Because they are a reasonably long lived organization with at least some rules and rituals that can be used as a base for theories. If they didn’t exist, a different organization would be used as the seed, or a fictional one would be made up. Unless you can think of a number of other organizations that for some reason aren’t picked on the same way? Church can’t be used quite the same, because they are to mainstream and inclusive, though secret societies within churches often get the same treatment.
While true, this doesn’t explain why specifically the freemasons are targeted.
Because they are a reasonably long lived organization with at least some rules and rituals that can be used as a base for theories. If they didn’t exist, a different organization would be used as the seed, or a fictional one would be made up. Unless you can think of a number of other organizations that for some reason aren’t picked on the same way? Church can’t be used quite the same, because they are to mainstream and inclusive, though secret societies within churches often get the same treatment.