Where does it say AirNZ doesnt employ aussies? Put your name in and you'll get an interview just like everybody else.
Can't speak of today, but I can attest that it twern't that way back in my day...
The pre-89 AN had an extraordinary number of Kiwis in its pilot numbers - someone once told me it was over 20%. (I'm sure someone will set me straight and tell me that wasn't so.) But back then, when a mainline job meant was something to aspire to, if you didn't carry a Kiwi passport, you didn't even get an interview with ANZ.