Sherm.
Jetstar international is all about Dixons 'vision' for low cost labour.
Nothing more nothing less.
It is massively cross subsidised by mainline. A good example is recently I operated a service to Honolulu which was supposed to be flown by JQ.
The JQ manager at SIT advised me that all costs associated with the replacement aircraft operation were borne by QF mainline. Imagine then, what would happen if they would have had to put these pax on other carriers if the cross subsidisation was not available. I am sure Air Canada or Hawaiian would not carry JQ pax free of charge.
Next time you are at SIT you will notice that most of the JQ check in staff are QF staff. JQ doesnt pay for this either.
Maybe you should go to the next QF group AGM though. You wont get anywhere with your questions, but it will be a good laugh for everyone else there.