You need to realise that people who work hard for THEIR money can do what they want with THEIR money.
And I personally will always import parts for what ever car I wish to build IF it's cheaper for me to do so and I would expect the people that actually use their brain to build a car would do the same! You could potentially save a massive amount of money doing it that way, money that can go towards other things.
I ran an online car parts website for a few years and I ended up removing it from the web for a few reasons, one was the local parts retailers IMO were overpriced. Why the hell would I buy a set of pistons (for example) from x stockist when I can jump on ebay even and buy the same things for a considerable amount less? Then you find the US car forum / Yahoo Japan Auctions and find the parts even cheaper!
I can agree with what you're saying to an extent, but the Aussie retails don't seem to be in touch with the exchange rates, when the Aussie dollar gets stronger they don't pass on the savings to their customers.
At the end of the day it's their choice to be a retailer, no one is forcing them to start that kind of business. No one is asking them to keep their business open even if its running at a loss. If they want to be more appealing to local customers then perhaps they need to look at what they're actually doing and seeing what competition is out there.
But I guess you'll be the dummy and pay more to support a local retailer rather than saving and buying from elsewhere - good for you.