They can’t broadcast your image without consent.

They absolutely can. The principle has been tested multiple times in court and the case law is very clear - anyone who is in a public place can have no reasonable expectation of privacy. If a photo is taken and published, or video is recorded and shown then anyone in the crowd is basically fair game.

For under-18s there is a code of ethics that means any responsible photographer will blur out the faces of anyone who appears to be a child, but even that's (probably) not enforceable by law.