Those in the western suburbs are unlikely to support a team...Parramatta Stadium was the basis of a non-ethnically based team and it failed...despite marketing heavily in the first years. Many in the western suburbs will not support the A league...it's time to get a new market and Aussie Stadium is that market.
All 'true' fans don't care were it is held...its simply just an excuse for a poor crowd attendance
Hiraldo is right as to the failings of Parramatta. Also, Northern Spirit were based 5km from Aussie Stadium and died on their arse. If you are going to blame geography, you would rule out the city too. Quite obviously, it was not a factor.
Also, in light of the ASA's decision to have one Sydney team, we must look at the city of Sydney as ONE market. You cannot divide it in to two for your convenience. I think there is genuinely two markets and that there should be two teams. But given that the ASA has ruled there is one, we must accomodate that large market as best as we can. You can't just say "if it's going to be one Sydney team, lets narrow it down and isolate most of the population" which is what your thinking is doing intentionally or not.
The people in the Western Suburbs will support the A-League. They are where the bulk of soccer fans are.