I guess they thought Australia would do what Britain did when Afghans 'hijacked' a plan and landed at Stansted. Despite reports to the contrary, that had all the appearance of a planned escape from a desparate situation.
Interesting that they didn't want to go back to Indonesia, but demanded to be taken to Australia. With the situation worsening in Afghan, I suspect this will happen more and more.
What I fail to see is the logic behind both Norway and Indonesia claiming it is Australia's problem - it is in fact Afghan's problem, which is reaching global proportions with Afghans now the largest refugee population in the world. Maybe the oil rich Islamic nations would like to offer a haven to any muslim refugees.
The western nations (does Australia qualify for that appelation as it is somewhat east of the Far East), can only support so many displaced persons, before the infrastructures collapse. Especially, as they frequently insist that their particular religious, custom and lifestyles have to be accommodated by the host-country.
What they have done though is make it far more likely that ships will try to avoid picking up what appear to be refugees (how many will die as a result).