I think that (and this is just my thought's, I don' know if it's the actual reason) Disney probably have some sort of contract with the Australian wholesalers for Disneyland and that is why we can't book through the DL website and why it is so expensive to book through Aussie TA's. Until that agreement date ends, then we will not get any specials, unless they are set by the Aussie wholesalers. I bet, once the agreement ends (assuming there is one), that Disney will allow us to book direct, Aussie TA's will lower their prices because they will be able to book direct and not be restricted to booking through Aussie wholesalers.
I know that one of my suppliers for my business of a product was ridiculous in price! I, for years tried to buy direct from the manufacturer, but could not because they had an agreement with my supplier that they would not supply to anyone else. Once that agreement ended, the manufacturer did not renew, so I (and other aussies) have been able to buy direct and now also have many suppliers in Australia so pricing is now competitive. It's like that for many companies, who give their product to other countries, to promote and distribute. So I bet that's the way it is with Disney and why to book through one of the Aussie wholesalers is SO expensive.
I know the wait times can be ridiculous, but it' still crazy. 3 Hours

If you were only there for two or three days, you would hardly get any rides in. I'd be running for that ride first thing (like everyone else there at rope drop) to get the shortest line as possible. No way this Aussietravellers would be waiting 2.5 to 3 Hours for a ride!