It's a scale thing, I think. In NZ if you are a bank wanting to introduce new technology for payments then you have exactly 5 other banks that you need to get on board. In the US there's many thousands.

e.g. The NZ banks jointly own the company that processes EFTPOS payments. A system like that could never emerge in the US. Instead, people have debit cards, which are manageable because they go through the credit card companies and there are only a handful of those.

But yeah, it's all incredibly primitive and fraud-prone compared to NZ or Europe (I've lived in all three).