If you were to measure it by other standards, QF group would probably not exist, or at least not have been able to get to the size it is in the USA as it would cross anti-monopoly/trust boundaries. The same issue with Telstra and many other previously state owned companies that hold way too much market share to be challenged by any competitor.
As said before the sheer size of these companies combined with the nationalistic rhetoric they pedal makes them very hard to combat in the Australian market. Even politicians and judges that are not corrupted by freebies would be very hard pressed to challenge these companies as they would face probable career destroying backlash. At least now QF is so on the nose with the public there might be a window of opportunity.
Its the same way companies like Coles get away with below award/minimum wage payments, by offering to take on unemployed as a sort of working unemployment benefit. The gov turns a blind eye to the wages and Coles hires lots of casuals and keeps staples at below cost to hide true inflation. Most of the casuals don't stick around so they are constantly hiring, which makes the employment stats look better, and the low cost of milk/bread makes inflation look better than what it is.