A national campaign, which started in Wanaka, to stop supermarkets giving out plastic bags is touring the South Island.
The GetReal campaign is being led by Wanaka Wastebusters employee Angus Ho, who is also the executive director of Hong Kong's Greeners Action group, which successfully lobbied for a similar change in that country.
Mr Ho said the campaign was "low-tech meets high-tech", with teams setting up a mobile street office in the main street of each town they are visiting.
The mobile office is a souped-up wheelie bin, which contains a lap-top and message board.
The campaign teams will be asking people to sign a GetReal letter which will be forwarded to two New Zealand supermarket chains, Progressive and Foodstuffs, asking that they introduce a small charge for plastic bags.
"A small charge has been shown to quickly change behaviour and reduce plastic-bag use by more than 80%," Mr Ho said.
Another GetReal team leader, Sophie Ward, who is general manager of Sustainable Wanaka, said giving out plastic bags encouraged people to use them.
"If the supermarkets gave away groceries for free, we'd all take home way more food than we actually need," Ms Ward said.
"If shoppers have to pay for a bag, even 10c or 20c, they're much more likely to change their behaviour and remember their reusable bags or find another way."
Almost one billion plastic bags were dumped in New Zealand landfills every year, and others littered reserves and waterways, she said.
GetReal campaigners visited Palmerston and Hampden on Monday and Oamaru yesterday.
They will visit Waimate and Timaru today, Ashburton and Dunedin tomorrow, and Queenstown and Alexandra on Friday.
A team will also be in Christchurch on Friday and Saturday.
