"In order to fly safely and efficiently, we need to calculate the weight, balance and fuel requirements of each and every flight ahead of take-off," said Air New Zealand chief operational integrity officer Captain David Morgan.
"To do this, we need to know the average weight of our passengers, crew and cabin baggage."
The airline added that all data was collected anonymously and results could not be seen by the data collection team or other customers.
"Although participating is not compulsory, we do really appreciate our customers helping out."
Economist Shamubeel Eaqub was also among those who were weighed, and said Air New Zealand staff were unable to share the number on the scale with him.
"I asked what weight I was. But the staff can't see it. Phew," he tweeted in response to Barry.
In 2003, a survey of 15,000 people by the Civil Aviation Authority found the average weight of New Zealand passengers and their carry-on baggage was 85.4kg.
Based on this survey, a "standard weight" of 86kg per passenger over the age of 13 was set by the CAA to calculate how many passengers a large plane can carry.
Airlines are also able to carry out their own weight surveys.