As an Australian (now an NYC resident), I am no stranger to the price gouging that Australians have had to suffer although I must say that how it is now is much, much better than it was 10-20 years ago. First, it's worth noting that US prices don't include sales tax. Australian prices include a 10% GST. Second, international companies will end up doing their accounting in one currency. For tech companies unsurprising…
Besides the illegality of it, what's to stop me being a purchase broker for an Australian and buying US products then shipping them to Australia to people for a huge discount?
And many US retailers are now shipping to Australia to take advantage of the price diff:
http://whirlpool.net.au/wiki/international_stores_that_ship_...