"Plastic bags are probably the smallest and least problematic component of the plastic that shoppers take home from supermarkets, and as yet we have seen no evidence that the supermarket operators are even thinking about addressing that."
Banning plastic shopping bags is simply an idea whose time has come thanks to public sentiment. The supermarkets are clearly anxious to be seen as responsible corporate citizens, but some of the more cynical say they have spotted an ulterior motive.
If a supermarket that currently 'gives' plastic bags to its customers, banning them will save a fortune, while selling re-useable non-plastic bags will no doubt be a very nice little earner.
Even if the cynics are wrong, getting rid of plastic shopping bags, welcome as it might be in some quarters as a step in the right direction, will have very little if any impact.
Images of turtles, in particular, that have eaten plastic bags are great publicity for those who deplore what people are doing to their planet, but the bags are a tiny part of a huge problem. And whatever supermarkets do, millions of people around the world will continue to make use of plastic bags. They'll just get them from somewhere else.
If there's a demand, as there will be, someone will continue to make them.
The scale of the plastic problem is almost beyond comprehension. Earlier this year the Tasmanian Institute for Marine and Antarctic Studies calculated that 38 million items of plastic debris had washed up on uninhabited Henderson Island, in the Pitcairn Group.
Over a three-month period, 17 to 268 new items washed up on one 10m stretch of beach each day.
Researcher Jennifer Lavers believes plastic pollution is as grave a threat to humanity as climate change, but it won't be addressed by a couple of supermarkets.
For a start, one of those supermarkets, Countdown, only accounts for around 20 per cent of the 1.6 billion plastic bags New Zealanders use each year.
The problem is that the plastic bag is extremely useful. Many who have joined the debate over the last week or two said they made further use of the bags they took home, most commonly as kitchen bin liners. When there was finally no further use for them they tended to find their way to the local landfill, generally inside a bigger rubbish bag.
Many said that if their supermarket stopped supplying bags they would buy them somewhere else. The common view was that as long as they were disposed of responsibly there shouldn't be a problem, and they were not prepared to countenance life without them.
Providing plastic bags that end up at a landfill are not allowed to escape there shouldn't be an issue. One suspects that very few find their way into the sea, where they can be mistaken for food and kill marine life. The same can probably be said for much of the plastic that gets into the marine environment. Unsightly yes, but, in larger forms, unlikely to be a threat to life.
It is smaller pieces of plastic that do the damage, and when it comes to shore birds it probably doesn't have to get into the water to do that damage.
The reality, however, is that few people, in developed countries at least, would be prepared to live without plastic. The issue will presumably be taken out of our hands when the oil runs out, but until that happens we will continue to use it, often unknowingly.
Plastic takes myriad forms far beyond those that we instantly recognise, and life will not be the same, or as convenient, as it is now if or when it finally disappears.
The problem isn't plastic; it's people who simply don't care. And that can't be fixed by a corporate policy to cease supplying one insignificant form of the offending material.
The huge effort made by volunteers on Saturday to clean up a stretch of 90 Mile Beach gave the disgrace of wilful pollution some perspective. We don't know how many supermarket shopping bags were removed from the beach, but it might well have been none.
The most common items found were probably glass and plastic bottles and aluminium cans, all of which are recyclable, at no cost. But it was other rubbish that revealed the extraordinary extent to which some people are happy to dump at the beach.
Fragments of rope and fishing nets, which probably came ashore, were common.
So were tyres, while one particularly ignorant individual dumped an entire aluminium shed. And there was plastic galore, ranging from bottles to fragments of goodness knows what. Whether it was dumped into the water or on land, it came from people. People are the problem, even if there are still some among us who try to shift the blame.
The Facebook reaction to last week's story about another huge illegal dump, on a roadside south of Kawakawa, was generally to describe those responsible as lazy, dirty, stinking mongrels and the like, but some blamed the Far North District Council for making the proper disposal of rubbish too expensive.
How's that for absolving the hopeless of all personal responsibility? They can afford to buy the beer but not to take the bottle it came in to a transfer station.
In fact much of the rubbish found down a bank on Ruapekapeka Road was recyclable, at no charge. All the owner had to do was drop it off at a transfer station, which the council is busy establishing from one end of the district to the other.
The fact is that it could have a transfer station on every corner and some people would still choose to chuck their rubbish over a bank or on to a beach. That's just the way they are.
One Facebook poster got it right last week - 'No respect for Papatuanuku'. Until that attitude changes, no one - not the council, not the supermarkets - will make any difference to the rate at which the environment is being polluted and wildlife is being put at risk. It is people who need to change, not the products they use in their daily lives.
Perhaps Countdown and New World will make a difference by ending their contribution to the plastic bag problem, although one has to ask why they can't just stop using them now, rather than phasing them out. But even if that does make a difference, it is addressing the issue from the wrong end.
All those people who have never flung a plastic supermarket bag over a bank or on to a beach will have to change their ways, when those who really should be looking at how they maltreat the environment probably never will.