I was once warned to not take a photo of some Blackhawks sitting at Point Cook RAAF base. (I wasn't actually going to, I was just warned about it)
The same 3 aircraft were at Avalon International Airshow 2 days earlier, but it was ok to take photos there as they were in "non-military configuration" versus the "military configuration" 2 days later. It's a big wank really.
That aside I did get kicked out of Wheeler AF base for taking a photo of an Apache