well public place is open to definition. A street is a public place, but the Qantas Club, an airport and a plane are not. Just because there are a lot of people there doesn’t make it “public” - it is owned or leased by someone.
Mr FM does a lot of street photography and that is fine to take photos of anyone. He still runs into problems, where he and a friend were taking photos and someone complained to a policeman and he tried to stop them, until they explained the law to them.....
There are also lots of caveats - e.g. the Darling Harbour precinct in Sydney has a ban on photography without prior permission. Now realistically no one stops a tourist taking photos, but they certainly invoked the rule near the convention centre. Security guards were quite aggressive at stopping photographs in the public areas at quite a distance away, even though people were asking to have their photos taken. Cosplayers love having photos. The majority of the photographers are like Mr FM - they don’t charge to take photos and provide free copies, even ones that have had a lot of work done on them to photoshop in appropriate backgrounds. It’s a hobby, they are not professionals, the security guards still refused to allow it, because of the Darling Harbour rule! Caused quite a fuss