I'm a so called 'entitled staff traveller' with a pretty decent onload/upgrade priority and it would seem to me that plenty of full fare paying passengers DO want to travel Qantas, especially the 380 services and even the so called 'loss making' FRA route.
The amount of trouble I've had in the last few years trying to get a seat, almost makes it not worth the effort after potentially be stuck away from home in a foreign city with no accomodation or flights and a closed airport...
I did say almost.
But having said all of that, every J class experience I've had, the cabin crew have always been excellent, attentive and great all round. Never had a bad or witnessed a bad customer service event.