I take a huge affront to this, as an Aussie who has never owned a car. Sure, you have to live in a city, like 90% of the rest of Australians.
And both London and Melbourne/Sydney/Adelaide have night buses.
Compare this with, say, Japan or Germany, where you can reach any point in the entire country quite comfortably on public transport. Now, given its vast size and the low population density outside the cities, I'm not saying it's feasible for Australia to ever have Japanese or German-style PT... but for better or worse, that's the situation today.
It's quite possible in many of Australia's larger cities.