I have, in my time, witnessed an extraordinary range of reactions to my asking for a doggy bag in a restaurant, following a half-demolished meal.

Embarrassment, bemusement, horror and a kind of appalled fascination are among the most common (although never from restaurant staff). I simply don’t understand why this is.

Neither, would it seem, does Huge Fearnley-Wotsisface, who has urged British diners to take their leftovers home with them. This should come as no surprise – Huge can regularly be seen scavenging food from bins, eating dirt with his fingers and picking up dog turds from pavements to put in his paprikash.

I exaggerate, but only by a little. Hugh probably takes any leftover bones home to make a stock. In fairness, though, why not? We throw away 20m tonnes of perfectly good food a year, a sickening stat when people still starve to death elsewhere in the world.

People wasting food makes my hair stand up on end, as I was brought up boiling up chicken carcasses, frying left over mashed potato and chucking a week’s worth of leftovers into a frying pan with some rice.

I take leftover food from restaurants that I intend to eat at a later date, but I’ll even take meat fat for my cat to eat, and bread to feed some nearby ducks – if there are any.

Frankly this is how it should be. Apart from it being blinding common sense, many of the problems associated with climate change – desertification, forest and bog clearance, and rapidly climbing amounts of methane in the atmosphere – can be directly attributed to our rapacious consumption.

And just as energy and water security issues are coming to light now, so will food security in the coming decade, as Western world ships all of its wheat production to volatile Ukraine – an acknowledged likely flash-point in any new global skirmish.

So, as the evidence mounts, it becomes not only a matter of common sense to ask for a doggy bag, it’s become a moral imperative.

It’s not that long since David Attenborough called for a return to ‘waste-not-want-not’ values to combat climate change.

And he should know a thing or two about the environmental problems the planet faces due to our obscene appetites, having spent 50 years schlepping around the globe staring at ants.

Why aren’t we teaching this in schools? Why, with my limited ability in the kitchen, am I pretty much the best person at cooking I know? And why on Earth wouldn’t people take home the expensive food they’ve paid for?

So, save some cash and save the world. Ask for a doggy. And, if possible, ask for the leftovers of the fat bloke next to you who only ate half of his steak. If you don’t want it my cat will give it a good home.

• Image by auxesis via Creative Commons

• A thousand apologies for the made-you-look header. I just couldn’t think of anything else.