I think we have said enough about the rules. In OP's defense, I just find that even these discount long haul NZ fares are not cheap. You just would expect them to at least earn something even in a partner programme and you would probably 99% of the time with another airline.

I often have the same problem flying a partner airline crediting to NZ as usually those earning 50% miles or less in another programme would simply be ineligible to earn Airpoints. And sometimes these fares are not even cheap. Would you pay double or even three times more to get an eligible booking class to earn yourself some token amount of Airpoints based on the pathetic partner chart?

I think NZ as an airline and Airpoints as a programme are going out of the way to make it difficult and their attitude towards partner airlines defeats the purpose of having a partner.