I had this same conversation just recently. Australia would be a great setting for an FPS really, it has a strong blend of natural and industrial elements almost at all times...it would allow realism without being brown and grey all the time.
That said, we're not important enough. We haven't 'hosted' enough battle, and we're an afterthought to much of the world. We can't even make the games ourselves because of the ridiculous cost and lack of support, and my guess is anyone that manages to break into the industry from Australia and reach a position of power will probably feel more antagonised by Australia than indebted.
In short, it would be nice as an environmental aspect, but we haven't done anything to deserve special treatment nor the means to make it ourselves.