Tesco, one of Britain's largest supermarkets, has revealed that it threw out 30,000 tonnes of food in the last six months. Customers throw out yet more. Appalling waste caused by the 'pile it high, sell it cheap' capitalist ethic?

Nobody likes waste, particularly those of us in the baby boom generation whose parents had lived through wartime rationing – or those who are old enough to remember it personally. We were brought up with the mantra 'waste not, want not'. Supermarket bosses are no different from the rest of us in that respect, but they have another powerful motive to avoid waste too: it is very bad for the bottom line. Why pay producers for food that goes unsold?

That is why Tesco has actually done a survey of what customers actually ditch, going through 10,000 dustbins in their research (ugh!). It seems that 65% of bagged salad is discarded, for example. The result of that? Probably, smaller bags being put on sale from now on. And clearer instructions on food packaging about how to keep it fresh.

There are many other reasons why so much food is wasted, though. In most cases it cannot be put into pig swill any more, because of the risk of animal diseases that might affect humans, though a bit goes to local zoos. Then there is the absurd 'best by' and 'sell by' labelling – you can blame government for that, of course.

Actually, we waste a lot less food than our wartime and postwar parents did. My mother's dustbin used to be full of potato peelings and the outer garbage of cabbages and other vegetables. Now, these are used and recycled and only the best bits reach our homes. Packaging too helps keep food fresh by protecting it from bruising and from the air.

The counterintuitive fact is that, thanks to capitalism, we actually have a system that produces food so efficiently that we don't actually mind throwing it out if it looks and tastes a bit elderly. If only we could spread this production system to other places in the world where food is scarce and expensive because it is not produced efficiently at all. Again, you can blame governments in those countries for resisting the market economy, and out own EU authorities for trying to protect their own famers behind trade walls, for that crime – not a crime against food, but against humanity.