As I see it, there are two separate and distinct issues here.
First is the $100,000 / 6 minute speech thing. As I said, I don't have an issue with ministers flying first class. Whether the trip should have been taken, given the PM and someone else from government were already over there and could have filled in for her, is another matter. She delayed the trip because of the 000 issue. That's an understandable reason for not attending the event, and having another person make the speech and attend relevant meetings instead.
The second, and the one I have an issue with, is unlimited first class air travel for family.
Why first class? They are not the busy minister, they are not in the public eye and they have no value to government. Why not economy like everyone else?
Also - you can argue that politicians spend a lot of time away from home and this is a necessary benefit.
If that's true, then a) why do 62% of politicians NOT use this perk at all, and b), why is it not limited to travel to Canberra?