Why don't the local NZ tech companies offer more, though? Mostly because they don't have the same scale, so the revenue per employee is much lower.
FAANG (as in, Meta, Apple, Amazon, Netflix, Google) make something like $1.5-$3 million USD per (white collar) employee (excluding Amazon warehouse workers).
Compare this to some well-known NZ tech companies (some of which even operate internationally!) Xero has revenue per employee of ~$150k USD. Pushpay maybe $200k USD revenue per employee. Datacom has revenue per employee of ~$130k USD.
It would bankrupt these companies to offer anything like what FAANG can offer, because they simply don't have the scale and revenue per employee to do so. Tech companies specifically have the rare ability to hugely leverage relatively few employees into huge revenue due to scaling, but only if you actually manage to scale. Most tech companies (probably even ones in the USA) don't have the kind of global scale and presence of the big tech companies.