Both projects are insanity IMO.
ANZ stadium definitely needs a fix up - it needs to be transfigured into a true rectangular stadium, and the first tier of seating should be steeper to get the fans closer to the action. But a full knock down and rebuild? Surely there's a more cost effective manner to improve the stadium? Not to mention the stadium is less than 20 years old!
Allianz - another ridiculous waste of money. The SCG trust came up with the spin that the stadium was unsafe, and so instead of doing an upgrade we're doing another full knock down and rebuild on a stadium that will only be full 2 or 3 times a year (ANZAC day, and A-league derby). All other marquee events (origin, grand final, bledisloe, socceroos) etc are played at Homebush, so I ask, do the Roosters, Waratahs and Sydney FC really need a new $700M stadium?
I'd argue Parramatta didn't need to be knocked down either, but that's done now, so I'll leave it.
The NSW government has been kissed in the butt with a rainbow via the property boom, and they have too much money to know what to do with. The bubble will burst eventually - let's just hope the government puts some money away for a rainy day.