Charge or ban might be necessary if trial voluntary scheme for recycling them to save environment proves unsuccessful.
Not only are plastic bags wonderfully convenient but they are free to most shoppers. It is little wonder, then, that New Zealanders use about 1.6 billion every year.
But there is a substantial downside to the bags. Usually, they are not durable enough for more than one use, and disposing of them has consequences for the environment, not least when they litter waterways.
The Government has heeded this danger through a new scheme to recycle plastic shopping bags, bread bags, frozen food bags and food wrap. This, it says, makes environmental sense and is cost-effective and practical.
The scheme will see drop-off points for the bags established at shops and supermarkets, from where they will be sent to a new Astron Plastics Group recycling facility in Auckland. All up, the Government is committing $1.2 million from its Waste Minimisation Fund.
If a trial proves successful, it is intended that 70 per cent of New Zealanders will eventually have access to a drop-off point within 20km of their home. Many of these people will have become used to accumulating a large number of the bags because they are not accepted by most kerbside recycling services.
For that reason alone, the Government's initiative is welcome. But it has not been greeted with widespread approval. That is not surprising because it puts the onus on people to deliver surplus bags to drop-off points. In some cases, that may be a forlorn hope.
If they have not taken the trouble to buy reusable shopping bags, what are the chances of them making the effort to use a drop-off point? For the scheme to work, there will have to be a considerable change in some people's attitude.
Additionally, other countries have been taking a stricter approach based on the damage the careless disposal of plastic bags can do, especially to marine life. This takes two forms. One involves a levy on single-use bags, a policy adopted, for example, by Ireland.
Already, a small charge is imposed in this country by Pak 'n Save and The Warehouse. Attacking the wallet of those who accept plastic bags without giving much thought to the consequences is obviously a deterrent. But there will be a big drop in use of the bags only if the charge is large enough to cause a rethink.
A ban on the use of plastic bags has, therefore, become the preferred policy in some jurisdictions, including a large number of American cities and counties.
Last year, California became the first state to impose a ban. As part of this, local manufacturers received financial support to help them make durable multi-use bags for sale in supermarkets and stores.
The Government says plastic bags make up only 0.2 per cent of waste going to landfills and 10 per cent of plastic waste. It implies that any steps beyond its initiative are unwarranted. But at last weekend's Local Government New Zealand conference, 81 per cent of the 76 councils present voted in favour of a Palmerston North City Council-proposed levy.
Those councils clearly view plastic bags as a far greater hazard than the Government. And they can see that they can be tackled far more directly than most of the country's litter. In time, the Government may have to come up with something more practical.