I can add some more things. But please no need to zap me for this.
Fuel is expensive. Food is expensive. Houses are expensive. And paychecks are smaller. Coming to New Zealand, an economic backwater, is a move backwards along most people's trajectory towards wealth. I'd only recommend to people who already feel like they have enough money and put more value on solitude, nature, safety, and lifestyle factors.
And you can get all of those things outside of New Zealand too. When I moved here I was stressed out and wanted out of the 'rat race'. But I could have moved to a lot of places in the USA that were better for me, I didn't have to come to New Zealand. Nonetheless, I like it here and put down roots so I'm not moving now. So when shit happens (e.g. COVID lockdowns, hate speech legislation, etc) I grin and bear it, and focus on my lifestyle lot, my sheep, my gardens, my equipment, and online stuff like nostr.
Also, you cannot exit the US anymore without an "exit tax" which basically takes everything you own and if it were this year's income! I'm stuck as a permanent US citizen because I didn't get out fast enough and I sure as hell ain't paying no exit tax.
The main reason things are more expensive is the shipping costs. We are way out in the ocean far from everybody.
The other main reason is that people are spread out a lot more, so each person has to pay for a lot of kliometers of roading and power lines and fiberoptic cables. In densely packed nations those costs are distributed over more people.
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