We very clearly don't, but whether it is a good or bad thing is a complex question.
Really! I get the impression that, in Australia, I live in a competitive economy. There are always anti-competitive practices that some industries try to put in place, and there is always room for improvement. Illegal practices of price rigging, price fixing and so on can be a problem in some areas, but generally I find that the choices of retailers in Australia, through the internet, are wide-ranging and vast.
If I find an overseas supplier who is prepared to sell a product I'm interested in at a significantly lower price than I can find in Australia, I'll calculate the additional cost of freight and GST if applicable, and buy the product from that overseas seller if the delivered price is lower than the best price I can find in Australia.
Almost invariably I find that books and prerecorded Blu-ray discs are cheaper from Amazon, even including the cost of the postage from overseas. Not only that, I get the stuff delivered to my letter box with no hassles, unless it's a large parcel which requires collection from the local post office.
However, perhaps it needs to be said that we are a pragmatic people in Australia. We don't waste everyone's time with inefficient administrative practices collecting small amounts of tax on items imported for personal use. Generally, if an imported item, including freight costs, is less than A$500, there will be no GST applied. If the value of the imported item is more than $500, then a 10% GST will apply, plus a small administrative charge.
The region coding of DVD and Blu-ray movies is a fine example of a wide-ranging anti-competitive practice. Fortunately, one can get around this by buying a region-free player. I would hope that the upgrade cost of Photoshop CS5 will be less than A$500 so that I will get it free of GST should I find it advantageous to buy the upgrade from an overseas supplier.