AFAIK - and this may not be true, I just heard it through the grapevine - is that one of the YSBK operators (since we were talking about Bankstown as well above), Aerospace Aviation went under partly because Bankstown Airport refused to transfer the lease to a new buyer who was willing to buy Aerospace Aviation at the time.
This was illegal, but the legal costs in forcing Bankstown Airport to transfer the lease made the sale commercially non viable.
So now Bankstown Airport are making zero rent from Aerospace Aviation, since they have gone under. Although this may be part of the master plan of Bankstown Airport, who knows.