THE latest annual audit of our food retailers’ plastic footprint, carried out by Greenpeace and the Environmental Investigation Agency pressure group, finds that supermarkets are using more plastic than they were in 2017. “We had hoped to see a much sharper downwards trajectory as strategies and targets bear fruit” said an EIA spokesperson, in a could-do-better tone.

But Greenpeace and the EIA might as well save their breath. Telling supermarkets that they’re not doing enough to cut their plastic use is like telling cats to stop killing mice. They can’t help themselves. Profligate use of packaging materials – plastic or any other materials – is hard wired into the supermarket modus operandi.

To truly comprehend the nature of the supermarket beast, we should think of them as dinosaurs: over-sized, lumbering, and incapable of changing. The over-packaging that’s so familiar in supermarkets – mushrooms in a plastic carton under cellophane, the shrink-wrapped swede, the flexible tray in the plastic wrapper that holds your baking potatoes or cherry tomatoes – fulfils several important functions for supermarkets.

For starters, it cuts the wages bill. Retailers need only employ near to minimum wage shelf-stackers, not brain-engaged sales staff.

Next, the tyranny of excess packaging forces all natural produce into one physical format that slots into its allotted shelf space.

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Forget the retail skill of the fishmonger or butcher laying out their wares, the greengrocer arranging fruit and vegetables according to what’s in season, supermarkets need everything they sell to fit into bags or trays of pre-ordained uniform dimensions. This is why supermarket rhubarb and celery, for example, are dry and brown at the end of the stalk: they’ve been cut to fit into bags – an assault on freshness – and in total defiance of their natural form.

Bags, boxes, and cartons enable every product line to have a bar code for checkout scanning. No need to pay people to weigh things; another wage saving. And bar code scanning keeps an eye on stock levels, so you don’t need anyone with any authority or expertise to order.

It’s all down to the head office computer. Stripping out human labour wherever possible, and making the few required posts as robotic as possible, is a key supermarket objective. Supermarkets aren’t interested in creating meaningful, skilled jobs.

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Packaging is also the sine qua non of “value added” marketing. For instance, there’s only so much we’ll pay for whole potatoes, even if they’re a boutique variety, hand washed in spa water by vestal virgins for M&S. But process them into microwave chips, or crisps, and the sky’s the limit.

The minute you process a basic ingredient then package it, you’ve created a licence to print money. Supermarkets have an incentive to sell highly processed, packaged products: they make more profit out from them.

In the fresh produce department, plastic disguises how unfresh so much of the fruit and vegetables really are. Case in point? Those “pillow packs” of salads that glisten under their plastic shield on the shelf, but then promptly wilt in the salad bowl.

And don’t forget the marketing guff. Where would that “low in this, high in that” advertising claptrap go if the product was sold “naked” or only minimally wrapped, with just essential legal weights and measures-type information?

Instead of being romanced by the promise of the sales pitch on the pack we’d assess the product with our eyes and our senses and reach our own conclusions. We’d be active not passive consumers.

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So I’m calling on Greenpeace and the EIA to stop feeding the idea that supermarkets can be useful partners in saving the planet.

Pitting one retailer against another in a kindergarten league table is naive, and ultimately pointless. This year it was Waitrose’s turn for a pat on the back as the best performer. Yet whenever I walk into Waitrose, I’m greeted by an ocean of shimmering plastic.

Supermarkets are part of the problem, not the solution. Ditch them, and you’ll cut your personal plastic footprint dramatically.

Don’t believe me? Try changing to independent shops, markets, farm shops, refill shops and other small food outlets. I guarantee your plastic waste will visibly shrink to a fraction of the supermarket equivalent.

Once you’ve seen that difference, there’s no going back.