Pedota-
With all due respect, you obviously just don't get it.
Staff travelers only get a seat IF THERE IS A SEAT AVAILABLE. So if there are no staff travelers, the airline gets nothing (that's $0) revenue for that seat. Staff travel contributes revenue the airline would otherwise lose when it has excess capacity on a route.
I can assure you that QF does not consider staff travelers when they set capacity on a route. ie. They don't send a 767 instead of a 737 just so the staff will get a seat. How you conclude that commercial pax "subsidise" staff is beyond me.
I can also assure you that staff travel contributes significant revenue to QF.
I'll do some math for you:
The first fare I seen advertised on the QF website
SYD - MEL one way $89
Now, the FULL LISTED PRICE for that sector is approx $385 of which staff pay a percentage. (and I know you know what that percentage is)
Of course you have to consider that for commercial pax to get discount fares they must be flexible with their travel dates and times. You must also consider that staff travelers must be even more flexible because they'll most likely be flying on the same low demand flights but with no guarantee of getting a seat.
Now, you see why allot of staff don't even bother using staff travel.
Back to my original statement: Staff Travel is not all it is cracked up to be!
regards, JA1