Philip Hensher: As long as food is cheap, we'll go on wasting it

My local supermarket sells chickens at under £3 each. They are not particularly nice – I guess they could only have been a matter of weeks old, and pumped full of who knows what hormones. They bear no relationship to a good quality chicken from a decent butcher, and are a third or a quarter of the price of one of those. The quality of life led by the animal hardly bears thinking about.

Still, at under £3 a pop, if you felt like an approximation of roast chicken, even if, like many people nowadays, you live on your own, it hardly needs to be thought about from the point of view of financial outlay. You pop it in the oven with some garlic and a lemon inside it, and take it out an hour and a half later. Slice off the breast and a leg, and there's your Tuesday night dinner.

Two thirds of the chicken is left, of course. You could have it cold the next day, or you could conceivably make soup out of the meat and the carcass. But let's face it; in nine times out of ten, you'll just chuck the rest away. After all, for under three quid, you've had one roast dinner, and that seems quite reasonable.

On every level, this has to be regarded as an obscenity, though nobody at any stage in the process is acting improperly. The consumer sees no reason to devote his valuable time to converting the remaining resources of something so cheap. The retailer sees it as a triumph that he can offer a product so competitively. The supplier has managed to keep his costs down through heaven knows what means – if you are paying less than three pounds, the supermarket is paying much less than that, and you have to wonder how little the farmer spends on food and welfare per chicken lifetime in order to make a profit on each animal.

They are all doing well, but at the end of the process we have the obscene spectacle of a chicken bred to taste of nothing much being picked at and thrown away because there is no good reason to do anything else. Food wastage, in this country, is of scandalous proportions. But the only reason to do anything much about it is the pressure of moral indignity. A lot of food is now so cheap that you might as well throw it away as spend your time preserving and reheating it in different guises.

The waste reduction agency, WRAP, has mounted a challenge to this repugnant situation. They point out that households throw away 6.7 million tonnes of food a year, of which half, they say, is still perfectly edible. In total, a third of all food purchased is thrown into the bin.

That seems like a horrific proportion, until you contemplate the cost which this represents. Wasted food, WRAP say, costs each British household between £250 and £400 a year. That, obviously, is not to be sneezed at, but when boiled down to the weekly figures, obviously most people would not worry too much about wasting between £5 and £8 a week. The figures are just too trivial.

The Women's Institute, however, is joining in with the estimable project of reviving the art of making little oddments of leftovers into something delicious you might actually want to eat. This is the sort of thing which, normally, you only ever read of in the aftermath of Christmas, with various unconvincing suggestions for turkey kormas and arancini con tacchino, or whatever.

But it really isn't all that long since anyone who ever set foot in a kitchen had an acute sense of what to do with the leftovers. I don't say that most British home cooks ever rivalled those legendary French housewives who were always said to be able to knock up a dinner for six out of some old fish bones and potato peelings.

But still there was always a decent repertoire of dishes which used up cooked meat and stale bread – shepherd's pie, bubble and squeak, bread and butter pudding and so on. A lot of these, if they have survived, are nowadays made with purpose-bought ingredients – how a 1930s cook would howl with laughter at the idea of buying fish expressly to make kedgeree or fishcakes.

There's no doubt, however, that cooking at all has become a sort of hobby, something which, however popular, remains a sort of special interest. And cooking with leftovers seems like an unusually abstruse sub-set of that special interest. The idea of saving £5 a week by carefully spending hour upon hour mincing, chopping, preserving, pickling and all the rest of it – hour upon hour which we have learnt to place a definite value upon – seems perfectly absurd.

Morally, it stinks that we should throw away food in such quantities, encouraged to do so by supermarkets which place completely ridiculous "sell-by dates" on their produce. But the encouragement of reusing food is never going to succeed nowadays. It looks, unmistakably, like the hobby of the underemployed middle-class person.

Food, nowadays, is historically cheap, and things which used to be luxuries, such as chickens or cream, are to be had for the loose change at the bottom of your pocket. The only thing that is going to reduce waste is the awareness of food's value; the only thing that is going to bring that home is the real cost of quality food. If people bought good food, at its real cost, it wouldn't be wasted.