What is a false religion? Is it a false belief? A belief in what? That one particular spiritual master or teacher's teachings are false whilst another's is not?
From what I can deduce from my reading of various spiritual-type books out there, the scribes or writers of these books write down either what they can remember about that teacher, or what they can remember they have been told by someone else about that teacher. So whatever eventually gets into the books might not be EXACTLY what was said by that spiritual master.
Then we have the power brokers; those with a vested interest to see that only certain parts of a particular spiritual masters teachings get into print. Anything that goes against their wishes is conveniently left out.
I suspect that the leading lights (prophets, saviours, saints) of all the major religions have been privy to experiences that you and I have not. The fact that people heard them and then decided to name a religion after them - these are the ones who might twist (intentionally or not) the teachings as they were originally given. And to say that people STEAL religion concepts from others is, to my mind, just reactionary simplistic thinking.