Does that work if they didn't say anything to incite acts that required policing or damage? Doesn't freedom of assembly mean freedom to call others to gather peacefully in a public place? I don't even get how needing a license to gather a large crowd is legal, denial of the license, delay of the gathering or financial cost are all restrictions on freedom of assembly. I would think that like freedom of speech, the government would need proof of imminent harm to others to stop you. You don't need a license to stream to a large crowd on the internet for example.