Aussies don't deserve to be ripped off, but you shouldn't have bought it at that mark up. If sony made zero digital sales in Australia because of their offensive 'because we can' mark ups they would be forced into making changes.
Unfortunately too many aussies don't care or don't even realize they are being ripped off. On xbox live there are also regional price discrepancies but they are far less severe, buying points at a discount pretty much negates the mark ups entirely.
Sorry to say this but you are part of the problem

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