Well, I'm not sure if this is useful or not, but here it goes.
I was getting to the point a month ago where I almost bought an aircraft for the first time, a Piper Pacer. I could afford to buy it, I could afford to insure it, I could afford to run it... I couldn't afford to store it. I'm a normal person and purchasing an aircraft was something I wanted to do out of love, completley lacking in any fiscal common sense, but my passion for flying is such that I was very keen. But it was just too much. Maybe in a few years... after everything has increased in price again
Now this wasn't at Bankstown, I can only imagine that BK would be worse in terms of aircraft storage. Paying thousands of $$ a year just to park an aircraft inside a shed, or even on a patch of grass is a bit of a killer. I'm not sure what the other fee's are like at BK, but they all add up.
I'm aware this isn't any great insight, I guess all I'm tryingt to point out is that GA might be busier in a private capacity if people weren't getting screwed out of every $ they have before they even get to say "clear prop." The passion is there for me, but its just too much.