Indeed there are. I _want_ to reward the authors of technical books, but there's no way I'm going to pay the outrageous prices Australian distributors want. It's still much cheaper to buy from Amazon and pay shipping from the US/UK to AU than buy locally. That assumes 1) you can find a bookstore and 2) they have the title you want in stock.
And Aussie retailers wonder why people are revolting and buying online...