You may be right and to what extent QF subsidises JQ is unknown, in all fairness they wouldn't have too if they wouldn't have to compete agains tree large government subsidised middle east carriers who don't seem to have an issue with flooding Australian skies with empty planes.
It's is fairly well know QF makes the bulk of its profits from its domestic arm and to an extend these subsidise its international operations, so I don't blame them for doing what it takes to enable them to be profitable. In the end the root of these inefficiencies lie in not allowing for a "true free market" where everyone can compete on a level playing field, ultimately this is at the expense of our local aviation industry.