Thanks for all the input guys. It seems like the unanimous decision is that I have to bite the bullet and pay the $70. To answer someone's question I'll be travelling to Gold Coast at the end of my trip anyways so I'd have to travel Gold Coast - SYD just to pick up a SYD - BNE, for me it's not worth my time since it will be essentially breakeven on the cost.

It's funny to see just how strange the fees and pricing is for the airline industry. I'm paying $70 so that I take one less flight. Logic would say that Qantas would want me to not take that flight so they can sell it to someone else.