I guess it depends on whether you think the rulings of an Australian court apply to you if you are outside Australia (even if you knew about the injunction)
In any case, I can't imagine it would be a good look for Qantas to go after them.
I've never seen it, but suspect a glitch. The $180 odd fare looks suspect to me....But also a bit odd that the return journeys have two different prices.
I wouldn't count on the Stay Free night being able to be used to remove the whole cost of one of the nights. For a room with Beach Club Access I'd expect a copayment if the room is even bookable that way
I have seen some level of enforcement at quiet times, but I would think impossible at others. In any case, most of the non-Hilton hotels (eg Accor) don't seem to have the choice between continental or full buffet.