I bring in stuff from OS regularly and none of my suppliers are going to register with the Australian tax office.. chances are that the GST will be applied at the point of import and the carrier will pay this upfront. This will then be passed on to the importer.. at a cost of course!
DHL already pay any fees upfront and then pass it on ... it aint cheap though as their admin costs are added.
It then becomes a choice.. pay the fee and get the goods or not pay and goods destroyed.
DHL..TNT..UPS etc will all do well out of this
if we had a labor federal goverment, you would think this is a favor for the postal unions