Just my opinion but I'm guessing that QF would also be hesitant to give internals crew positions as then they would be responsible for re-employing for the positions left open.
I imagine there are a lot of applicants from many different departments, and if they were to give these people preference over externals they would be making a lot more work for themselves.
I'm not saying it's right, just that on the business side of things you can see why they would do it.
And if that was the case you would want to think twice about joining the company in any other department other than the one you wish to work for. It's very sad that loyalty to the job and company you work for is a thing of the past, just faceless numbers that can dispensed at will now.
I'm glad I got to enjoy some of "the good old days" when you felt you were the company, and that every person mattered.