Even if that weren't the case, I don't know about the rest of the world but in the UK, at least since the Russell Davis reboot, Doctor Who is mass market.
Yes the people you're talking about exist, but they're not the majority, they're not even that big a minority (though they're very vocal). A network is always going to go where the money is and that's with the largest number of people.
Thus, Australians have to endure an entire week of UK/US discussion before they can see an episode.
I imagine many fans will continue to pirate.
Why will Australian fans continue to pirate now that the show will be available legitimately on ABC's website 50 minutes after UK transmission?
Yes, watching it on a PC/tablet/phone is not the same as watching it on a TV, but pirated versions suffer from this as well.
And the worst part is, when you finally see it: you have no one to talk to! The world already discussed, spent a week fanboying out about the episode! They'll spend the week discussing yet-another new episode, while you hide trying to discuss a week-old episode without learning new spoilers.
It keeps you a week behind the world on discussion and prevents you from being able to use any fan media during an active season without having big plot points spoiled.