Regarding ground staff pay, that is slowly being reduced (along with FAs) via subsidiary companies (QGS) which employ new rampies -- and they earn roughly the same (or less) than other competing ground handlers around Australia. In terms of airport customer services - most foreign airlines employing local staff in Australia (eg CX/JL/SQ etc etc) use the QF EBA as the standard for their employee's Ts & Cs.
The same for FAs - both domestic and LH FAs are employed by subsidiaries with starting rates from around ~$45K I believe. Consider that an SQ FA will earn roughly the same, and you can see that wages aren't particularly extravagant.
That being said - ground staff in Australia (with QGS earning <$20/hr) are likely earning at least 2 or 3 times more than their compatriots lugging bags in SIN/DXB/HKG... but then so is the check out chick at Coles.
Australia is a high cost country - we enjoy a high standard of living, and higher wages naturally come along with that.
As mentioned by others, pre GFC, QF was expanding, making billion dollar profits, and wages weren't that much less compared to what they are now. So if QF were able to make bumper profits with basically the same cost structure -- staff wages aren't the problem..