It’s not just far, it’s far away from everything, including all the major trade routes. In Europe and Asia, a lot more goods are produced close by, and if you ship a product to any country in Europe or Asia, there’s a lot more people to buy it, and a lot more markets close by.
And there are lots of regulations too. For example I sold an oil burner light on eBay to someone in NZ (didn't actually know as there was a UK address that forwarded the package) and I included some oils for free...
Big mistake. Package was returned and I had to remove them.
My only point being it's a poor port in part because of its delicate ecosystem, which necessitates very strict regulations.
Add a layover and you could easily be at 20+ hours (which is common since NZ is small so there aren’t that many flights). Europe is well over 24 hours even to the major hubs.