I think you will find the Kiwi Government like most (but not all) Governments were not keen on sending in Military aircraft to bring back people as the situation in Thailand was more an internal political situation not a war zone (like Lebanon).
From what I have heard, many Governments who did send in an aircraft, charged people for the privilege of getting on the flight (regardless of whether they had a ticket for another airline or not).
If the Governments send an aircraft to fetch people it sets a precedent for other situations. At the end of the day, people should have travel insurance for situations like this and just buy a ticket and recover the money later.