Your comments above and also in the Tiger Island thread are showing you must have trouble processing information.
The parks could afford to spend $16-$18 million dollars on a single ride 10 years ago because everyone stepping through the doors was paying $70 a visit, or an annual pass set you back $300!! Now 70% of the people walking through the doors are paying less than $100 a year for the privaledge.
Then there was also that little thing called the Global Financial Crisis - heard of it?? Australia may have got off lightly, but the parents companies, shareholders, manufacturers and suppliers are largely based overseas - many of those in countries whose economies plummeted - if you dont think this has an impact on spending your crazy.
You're post was flawed from the first 10 words when you related 'high prices' to entry into Australian theme parks. The issue is that there are too many CHEAP annual tickets. Get rid of VIP passes and go back to $250-$300 per person for an annual pass, none of this buy 3 get 1 free crap, and we'd be halfway there.
Until then, be happy that we are getting any new offerings at all.