Well I honestly see no reason to try and disprove religions. Some of them do have fucked traditions, yes, but trying to invalidated one's faith is just sad.
As for the Santa part, I can't really argue against that. But for my own sake I'm going to keep pretending he's real, as that's more comforting that the thought of a crackhead breaking into my house and stealing nothing but cookies.
Financial gain? We're speaking of religion, not vanity churches. If people want to believe in something above themselves, you have no right to say otherwise just because you yourself believe against it. And the fact you believe all religion is directly tied to money really speaks numbers to how you see things you don't like.
There would be no religions if there wasn't churches pushing them. People can believe in the tooth fairy for all i care. Doesn't make it true or possible.