Doubts are being raised about whether supermarkets' ban on plastic bags will make a difference to widespread plastic pollution.
The two main supermarket chains in New Zealand have now both committed to phasing out single-use plastic bags by the end of 2018.
It said an overwhelming majority had voted not only to charge for the bags but to ban them altogether.
Its North Island chief executive Chris Quin said the survey originally did not have the option of getting rid of the bags completely.
"In hindsight there were probably actually more options we should have put in that vote and more room we should have given customers to give us feedback," he said.
"They came in every way they could, through social media and through email ... basically saying they did really care about it but there was more to it than just a levy as a sort of long-term way of making a difference."
Mr Quin did not promise other Foodstuffs-operated supermarkets such as Four Square and Pak'nSave would be following suit, but he was hopeful they would.
He said he was aiming to eventually reduce all the plastic used in supermarkets including for fruits and vegetables and for packaging.
Massey University lecturer of marine biology Daniel Godoy said that was a good thing, but there is plenty more to be done.
"Retail products, things that are wrapped up in multiple layers of plastic for no other reason than to make the product appear bigger and therefore more sellable on the shelf, is one thing that I am really concerned about," he said.
"In terms of packaging large items which get shipped overseas ... or come from overseas packed in huge amounts of plastic, is also another aspect that should be considered."
Dr Godoy said plastic was extremely harmful to the marine environment; not only for fish and animals who ingest or get tangled in it, but also through the toxins released that pollute water.
Environmental activist group Greenpeace said it was very heartening to see the public driving supermarkets to change their practices.
But plastics campaigner Elena Di Palma said what would really make a difference would be if the government got behind the cause.
"We are challenging the new government to take this on and to match the ban that the New World and Countdown have now committed to and put in the regulation that New Zealanders want," she said.
New World will also be giving away two million reusable bags to its customers this summer and in February it will introduce a voluntary 10 cent donation per bag that will go to environmental causes.
It would also continue its 5 cent rebate for reusable bags in its North Island stores and expand its soft recycling programme.