I'd guess it's because fuel prices became something people were paying a lot more attention to, from both the general public and the government. When people go back to just going to the nearest station instead of checking online for prices and the government stops feeling pressured by fuel prices being in the news regularly I suspect the old games will start reappearing.
I will note that the local price differential that usually exists around me has markedly decreased - typically fuel gets noticeably more expensive when you drive the couple of km from Queanbeyan into the ACT (can be up around 20c/L difference) but it's currently pretty comparable.