system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does shipping something from the USA to NZ have around triple the price of shipping a similar item from NZ to the USA?

It costs me around $15 (NZ) to send an item from NZ to the USA, but around $30 US (which is about $45 NZ) to ship a similar size/weight item the other way.  Is this perhaps due to some sort of taxes behind the scenes?
gpt
No it is not an import tax thing, it has everything to do with the volume of things going what direction. There are a lot of tings that ship from NZ to the US. There are very few things that ship from the US to NZ.

While you may think that ships would just move back and forth, that is not actually how shipping works. Ships will run a circuit of destinations, and shipments that have low volume must make up the cost with higher costs of shipping.