There's always been an expectation of truthfulness in communication: We don't allow people to go around claiming that Pepsi causes AIDS, or cures cancer. You're not allowed to claim you're collecting for a charity, and then keep all the money for yourself. I doubt you'd be terribly okay with me claiming that you're a murderer and asking how much that biases your stance.
(Genuinely trying to understand if there is something that makes this different from any other sort of fraudulent communication - I don't see people defending the other stuff under the guise of "Free Speech", and I'm not clear why this would be different)