My own experience is that conspiracy theory can be a cover for something a lot more narrow. A few of the more extreme religious fundamentalists I know – ones who are super pious, and also birthers, truthers, believe that the swine flu was made by the gov’t, hate Lincoln, etc. – are pretty much attaching themselves to conspiracy theories because their more narrow interests (i.e. supporting Serbian genocidal maniacs) aren’t even remotely appealing to others.