"People can download their passes on to more than one device, so some are requesting more than one My Vaccine Pass.
"People vaccinated in other countries are also getting My Vaccine Passes, which will explain why more passes have been issued than there are people who have been fully vaccinated in New Zealand."
Vaccine passes are valid for six months. Booster shots are underway for those jabbed more than six months ago.
The passes aren't needed for basic needs such as shopping at supermarkets, accessing healthcare or using public transport but under current traffic light settings must be used to enter places such as hospitality, events and close-proximity businesses such as hairdressers and gyms.
They work by providing businesses with a QR code to scan using the NZ Pass Verifier app, which confirms vaccination status.
While some Auckland restaurateurs, who had been unable to open their doors since August 17, called this month's re-opening "a dream come true", others were unable to take advantage of the relaxation in rules because of lack of staff.
Sumo Sushi owner Kiwoon Keun told the Herald said he couldn't open his 150-seat restaurant because it'd been "impossible to find staff" to meet the new enforcement rules.
"I only have two staff, and in order to police vaccination passes of customers I need to recruit at least two more people to stand at our two entrances, but there is no one," he said, noting his pre-pandemic workers were usually international students or people on working holiday visas, both now shut out by the closed border.
"It is heartbreaking to see other restaurants opening up while I am forced to keep operating as a takeaway."
