Do you remember Peak Stuff? We reached it back in January, if that helps jog the memory. Or at least that was when Ikea’s chief sustainability officer Steve Howard declared that so many people now have so many material belongings that we’re reaching saturation point. Drowning in stuff. Sick to the back teeth of stuff. (Apart, obviously, from those who don’t have enough of even the most basic stuff, including food and a roof over their heads, but then they presumably are not Ikea’s target customers.)

The gist of it, anyway, was that awareness of the environmental and human costs of making things is making people faintly uneasy about buying whatever they crave and then swapping it for something new the minute they get bored.

Well, that was then, and this is Christmas. Once again Britons are set to spend record-breaking amounts, and festive inflation – or the invention of spurious faux traditions at which to throw money – remains rampant. This week brought news of some fresh hell called the Christmas Eve box, a supposedly emerging trend for parents to give kids a box of small presents on 24 December as a kind of hors d’oeuvre to the Christmas Day stocking, for the child who just can’t wait until 5am. A special personalised box for just this purpose – and remember, that’s basically an empty cardboard box with a name glued on – costs around £2.50 before you put anything inside. Peak stuff is still light years off for some, it would seem.

And yet Howard was surely on to something in describing this new queasiness about consumption. Desire for many things wanes with age, and it would be surprising if the fact that we’re an increasingly elderly country did not impact on the way we consume. What can you buy the average 87-year-old that they want but don’t already have? Nobody really wants to make room for yet more pointless stuff in a house that’s already overflowing, especially if before long they might be downsizing. But that slightly impatient feeling of satiety, of no longer being able to think of anything you particularly covet – or at least, nothing money can realistically buy – sets in long before old age.

‘Womble Christmas has turned shopping back into a game; part treasure hunt, part initiative test.’ Photograph: Don McPhee/The Guardian

It’s a hideously middle-class problem, born of spoilt affluence mixed with a vague anxiety about consumerism, and crucially sharpened by eco-guilt. Howard wasn’t saying that people had stopped actually wanting new things, simply that they don’t like to feel as if they’re draining a finite supply of raw materials just to buy things they don’t need. The trick was for retailers to find ways of assuaging their consciences – in Ikea’s case by recycling and repairing old products (some of its stores overseas will now buy back shoppers’ old unwanted furniture). It’s a case of at least paying lip service to the oceans of unwanted stuff already out there – which brings me to an experiment that has, quite unexpectedly, put the thrill back into Christmas shopping this year.

Back in November, my mother unilaterally declared that she now had more than enough stuff, and that arguably so did all the other adults in the family. And from that emerged the charity shop challenge; no grownup to spend more than a tenner this Christmas per sibling, parent, in-law or jaded adult child (kids, whose desire for stuff remains cheerfully inexhaustible, are exempt) and crucially everything had to come from charity shops.

It’s not a joyless fatwa against presents, but against stuff, the definition of which is that endlessly acquiring new versions of it doesn’t actually make you happy, with the bonus that all the cash goes to good causes rather than to Amazon. The challenge element comes in ensuring it’s something the recipient might actually like, while making good use of whatever you find.

Eyes did admittedly roll at first over what more cynical elements in the family are calling Womble Christmas (sorry, Mum). Goodbye, ordering everything online at midnight; hello, endless afternoons of rummaging patiently through jumble. But little by little, Blue Cross shop by Oxfam store, my attitude has changed.

It helps that charity shop staff tend to be cheery types, if only because so many of them still aren’t entirely sure how to work the till and need to make small talk while stabbing hopefully at the buttons.

Another breakthrough was stumbling across the Facebook project Knickers Model’s Own, in which the blogger Caroline Jones marked her mother’s death from cancer by choosing and photographing a different outfit from the rails of Cancer Research UK shops every day for a year. (Hint: it’s now a book, all profits to cancer research.)

But it’s more that Womble Christmas has turned shopping back into a game; part treasure hunt, part initiative test. You can’t just set off with a list and a grimly determined expression. You have to use your imagination, see the potential in whatever turns up – and the quality of things that occasionally do turn up seems extraordinary, in the age of eBay. In some cases giving it all away to charity shops is clearly a guilt-free way of emptying overstuffed cupboards before gleefully filling them back up again, which rather makes Steve Howard’s point for him.

For a while, it looked as if the answer to the consumer guilt he identified might be for physical stuff – music collections, books and film – simply to go digital, shrinking its environmental footprint. But that transition may not be as quick or as smooth as expected, with sales of vinyl currently trumping downloads, and anyway it doesn’t cover everything.

Predictions that in future we’d rent the bulky stuff, such as cars and clothes and power tools, from one another rather than buying it outright lost their idealistic gloss once the so-called “sharing economy” became synonymous with Uber, Airbnb and job losses in the conventional economy. But then that’s the problem with middle-class anti-consumerist movements; they often end up being accidentally anti the thing that keeps poorer people in jobs. Small, considered rebellions against joyless excess seem a more sustainable option all round.

And the most striking thing about junk shops is how little junk, in some senses, they contain. They’re stuffed full of things that did at least once have a purpose, even if that purpose is forgotten or unfashionable now, rather than selling themselves on witty design, aspirational branding or easily exhausted novelty. You either want these china teacups and this tennis racket badly in need of re-stringing, or you don’t.

And that’s the thing about shopping. If a month later you can’t even remember why you wanted something, then however expensive or desirable it once was, it’s just stuff. If 10 years later you’re still telling the story of how that picture was unearthed from under a pile of old junk in some sleepy market town – well, that was a present. Happy Christmas.