Originally Posted by
Kiwi Flyer
Air NZ is not the only airline to do this. The reason they want to reissue BPs is so they can check for themselves passengers eligibility to enter NZ (the country) and avoid being fined (plus the cost of returning ineligible passengers back to origin). Presumably Air NZ incurred enough costs/hassle in the past to warrant the effort required in reissuing boarding passes.
Exactly, they don't need to re-issue the boarding pass but they do need to do the passport/doc check. IME United does a document check when connecting onto them before an international sector, but they don't often issue a new boarding pass (though it has happened).