"If someone is in a public space, like a park, beach, or sidewalk, it is legal to photograph them. They shouldn’t expect privacy laws to prevent them from being photographed. That means a street photographer can publish candids taken in public spaces, as long as those images are only being used for editorial purposes."
It'd be impossible to photograph a protest, rally, sporting event, or basically any long shot of a public area if you had to get individual consent from every person in the frame.
I suspect there's a bit of nuance there which hasn't been identified here yet. Perhaps to do with whether people are background or immediately identifiable, or and active part of of what's going on. I know consent forms are a part of television recording when talking to people on the street (otherwise they blur faces), but I don't think they bother to get everyone in the background to sign.
