Freedom campers like this German family tend to spend more and stay a lot longer than visitors who don't backpack or camp.

Under-fire freedom campers spend more and stay longer on average than other tourists.

Ministry of Business, Innovation and Employment (MBIE) analysis of visitor spending over the past three years found visitors who freedom camped spent about $260m a year, or about $4880 a person on average.

MBIE manager sector trends, Peter Ellis, said online comments criticising freedom campers as freeloaders were unfair.

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"Certainly it's not how we'd describe them . . . We do think that on average they spend more per trip to New Zealand than the average visitor does. That's likely the result of them staying longer.

"They might not be spending as much on accommodation, but they are spending on food, retail and transport."

The visitor spending statistics are based on credit card and other data, and Ellis said they captured all spending other than airfares. It was not possible to match that with accommodation, so there was no data on what different types of visitors bought while they were here.

But freedom camper budgets were bigger than those staying in backpacker lodges or camping grounds, and their spend far surpassed the $2,814 per head spent on average by visitors who used other forms of accommodation.

When length of stay is factored in, freedom campers, backpackers and other campers are a frugal bunch, spending about $100 per day on average compared with $156 per day by other visitors.

Ellis said freedom campers accounted for about 3 per cent of total annual spending by international visitors, which reflected their relatively small numbers.

" . . . 60,000 seems like a lot, but out of more than three million visitors it's quite small."

However, freedom campers stay 48 days on average, a month longer than international tourists who did not camp or backpack.

There was no measure of the impact freedom campers have on the environment or their use of facilities such as toilet blocks, roads and reserves, Ellis said.

"There has been talk of working out how many days they are here and apportioning a share of the total cost of roads etc. . .but no estimate has been done."

Tourism New Zealand chief executive, Kevin Bowler, said backpackers and freedom campers made a substantial contribution to the country's economy and should be made welcome.

"We always advise campers to use holiday parks, DOC camp grounds or other suitable designated overnight camping areas. It's in everyone's interest to minimise the impact of tourism on the environment and New Zealand's communities.

"It's disappointing that a tiny number of people are disrespecting the environment and are effectively spoiling it for everyone else. We don't condone that behaviour and fully support councils in taking action."

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