All those teams had decades to build up geographic identities.
Why the hell would anyone follow the Perth Sharks?
Maybe pick up a lot of people who may like the name Perth. Those who want to be different from the crowd. Those who may not be nut case WCE supporters so a new team might appeal. Maybe join a new team that doesn't rip their members off because they have the market by the throat.
I guess thats just a few.