What Role Do Nutjobs Play In Declining Church Attendance

I don’t know if there is a nicer way to characterize something like this:

There is, in almost every church of more than, say, 100 people, at least one person like this. The rambling conspiracy nut who is convinced that some coincidental use of various symbols actually means that a random artifact of modern life is actually satanic. Now, the people who promote these nutty conspiracies rarely get time at the pulpit, but since they are usually very involved in the church it seems that there is often little or no effort made to correct them, their paranoid rambling is passively tolerated. Of course eventually they will express their insane views to nearly everyone in the congregation, and (hopefully) those stronger, more mature members will likely just roll their eyes. Nonetheless one has to worry that a casual visitor or a younger person might look at this and decide that, if that person is allowed to actively peddle this sort of wackiness, then what kind of place is church? Are we prepared to confront the conspiracy nut jobs in our midst and have them shut up?