"Telephoto lenses on beaches - ANYWHERE - are unnecessary. Unless you've got release forms for everyone on the beach..."
Who are you to dictate what is necessary? What if I wanted to photograph surfers? or wildlife native to the coastline? Or, since they are people in a public place even the beach folk would legally be fair game.
Furthermore, in the uk I wouldn't need a release form unless I was going to use the photos for commercial gain - is this different in Australia?
Finally, surely with a telephoto, I'd be able to isolate people in shot more effectively than with a non-telephoto, so I'd be less likely to need a release form for everybody on the beach, since they wouldn't be in my photo...