There has been a lot of research on the types of people who believe conspiracy theories, and their reasons for doing so. But there's a wrinkle: My colleagues and I have found that there are a number of people sharing conspiracies online who don't believe their own content.
There are several types of this sort of conspiracy-spreader trying to influence you.
Coaxing conspiracists—the extremists
In our chapter of a new book on extremism and conspiracies, my colleagues and I discuss evidence that certain extremist groups intentionally use conspiracy theories to entice adherents. They are looking for a so-called "gateway conspiracy" that will lure someone into talking to them, and then be vulnerable to radicalization. They try out multiple conspiracies to see what sticks.