Addressing the initial issue of employees 'stealing' food that is to be thrown away anyway.... and what constitutes 'stealing'.....
I once worked for a company that had a big problem with catering/crew meals etc going missing... they decided to have a set area aside for 'take what you want'... anything that was unable to be used again on another flight and would normally be thrown away would be put in here, anything in there was fair game for anyone wishing to take it home... get caught taking anything from anywhere else and suffer the consequences....!
Surely QF could have some sort of way of doing this... everyone knows groundies/rampers etc scrounge the biccies on turnaround... at least if there was some way they could 'control' what the ground staff (and others) take, then the problem would likely be reduced a great deal... people would feel they can have 'something'... without the problem of knowing 'what' to take... and the company would know that only the 'leftovers' were being taken...