Can There Be a Fake Religion?

Before a meeting yesterday, I was glancing around the room at some of the older books in our religion department's library. One that caught my eye was called The World's Great Religions. I proposed other volumes for the series. For those that just missed making the first volume, we'd have The World's Pretty Darn Good Religions and of course one for The World's Really Crappy Religions. My colleague suggested one for The World's Fake Religions, and talked about an interesting student presentation in her Philosophy of Law class a few years back that examined the fourteen conditions put forward by a British court that define a religion and why Scientology fails to meet them.

I'm not interested in a discussion of the details of Scientology here, but rather am fascinated by the phrase "fake religion." Could there be such a thing?

A fake religion would not be a false religion, that is, one whose foundational beliefs turn out not to be the case. That would still be a legitimate religion, just one that turned out not to preach the absolute truth it thought it had. It would have to be something else.

What about the Church of the Flying Spaghetti Monster? Again, that seems not to fit either because it is not meant to be a religion at all, but rather a set of absurd doctrines and artistic artifacts that mirror those of legitimate religions in order to create a logical equivalence between something designed to be clearly irrational to be used in a larger reduction ad absurdum. It is not a fake religion, but a religion-like non-religion.

If people at the top do not believe, but there are legitimate faithful below, is that sufficient to make a religion a real religion? Can there be a fake religion?