No, but the 14% drop in the AUD vs the USD in the last several months justfies the price difference on top of the tax built in as a buffer.
Compared to the USD right now Aussies pay $44 more for the 16GB. In three months time that could be $0. In six months time that could be negative.
Yes, Australians pay more for the iPhone, particularly in Canada where it's the cheapest in the world right now, but compared to everything else (ie double on a copy of Windows, triple on a copy of Photoshop), Apple's AU prices are very good.