Ugly as this is, if this is something that Qantas staff feel they should be doing (I imagine this isn't the first time) then perhaps it's just as well it was done to a passenger with such a high profile as it brings the ugliness out into the open.
I'm sure the majority of Australians will feel just as revolted as I do.
It is a strange, probably psychological, barrier though - allowing prosthetic legs into a cabin and not allowing someone else's chair.