Firstly, they are few in number - just 40 in the Christmas Island detention centre and around 500 in total facing deportation from Australia out of a estimated total of around 600,000 New Zealand citizens living there.
Secondly, almost all of them face deportation because they have committed serious crimes and because they are being deported upon release from prison. Many of them are appealing their deportation order. This is why they are in detention centres.
Thirdly, Australia, like most countries, does not deport its own citizens. We have heard sob stories of people who have been in Australia many decades being deported back to New Zealand, but these people must have been unwilling or unable to obtain citizenship or there would be no question about them being deported. New Zealanders can apply for permanent residency and then citizenship after just twelve months in that country. There are eighteen different categories under which New Zealanders can apply and it is actually encouraged by the Australian Government because they want New Zealand immigrants to be fully functioning members of Australian society.
Finally, New Zealand citizens do not qualify as refugees. The United Nations High Commissioner for Refugees defines a refugee as someone who, "owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his nationality, and is unable to, or owing to such fear, is unwilling to avail himself of the protection of that country." That definition does not apply to these New Zealanders.
I have written on this blog about my liberal views on immigration (most recently here and here). I think it is very much in any country's interests to accept all manner of people who want to live productive, independent lives in a new home and I have the utmost sympathy for those fleeing persecution in their original countries. But I accept that it also a country's right to deny entry or to deport those who are determined not to live productive, independent lives. The only issue I have with Australia deporting these undesirable New Zealanders is that we have to accept them back here.
Perhaps we should put them on the Auckland Islands.