J* subsidy
The only reason that J* is making money on their Japan routes is because QF mainline has a contract leasing all the freight capacity on the flights. This is guaranteed income on every flight despite the fact that few flights carry any freight. This is just a way of subsidising and keeping the paperwork look right.
Also, Qantas catering divisions were instructed on what price they would tender for the J* intl contract - well below normal commercial rates and below cost.