This is by no means an official answer, just personal thoughts.
At the moment, there is no mechanism for ending a PR visa even if the person is now living away from NZ, unless the holder has committed some serious crime. Every so often, a rumour goes round that the rules are going to be changed, but that's all it is, a rumour. The matter hasn't even been under official discussion. This is, after all, NZ law, and it would take a decision by the government to bring in any change.
As things are at present, I don't *think* anything you say to the bank would be/should be automatically passed on to INZ, either.