TV advertising used to work like this: you sat on your sofa while creatives were paid to throw a bucket of shit in your face. Today you're expected to sit on the bucket, fill it with your own shit, and tip it over your head while filming yourself on your mobile. Then you upload the video to the creatives. You do the work; they still get paid.

Hail the rise of "loser-generated content"; commercials assembled from footage shot by members of the public coaxed into participating with the promise of TV glory. The advantages to the advertiser are obvious: it saves cash and makes your advert feel like part of some warm, communal celebration rather than the 30-second helping of underlit YouTube dog piss it is.

Witness the current Oxo Factor campaign. According to the website: "Has your Family got the OXO Factor? It's 2009. There's no such thing as 'the OXO Family' any more. We're all OXO Families! That's why we asked you to film your family performing the script for our new TV ad, for the chance to see yourselves on TV, alongside some of Britain's other brilliant families." Or "other insufferable arseholes", depending on your point of view.

End result: a bunch of wacky-doo show-offs titting around in their kitchens, each reciting the same script, which they're not allowed to deviate from. They can perform it "ironically", and indeed they all do, which somehow only makes it more horrible still: the Oxo family of 2009 may display faint traces of corporate-approved subversion, provided they adhere to the corporate-approved screenplay. Lynda Bellingham's fictional family of yore might've been insipid, but at least they weren't willing participants in a macabre dystopian dumb-show.

Phone ads are worse. Everybody's "brightdancing" according to The X Factor break bumpers. "Brightdancing" consists of shooting a video of yourself waving your mobile around while being filmed by a Talk Talk website gizmo which turns the glare from your mobile's screen into a ribbon of light. It's less creative than choosing which colour iPod you want for Christmas. "Brightdancing". Jesus.

Then there's Josh, the simpering middle-class mop who's apparently "forming a supergroup" for T-Mobile. According to the official story, Josh was strolling down the street one day when a T-Mobile film crew asked him what he'd do if he had free texts for life. Rather than pointing out that "free texts for life" means dick-all in a world containing the internet, Josh burbled something about forming a band. A few weeks later and gosh oh crikey that's precisely what's happening! And we're all invited! Hey everyone! Join Josh's Band!

As well as TV spots recounting the irritating story of Josh and his "volunteers" (Yikes! They're busking in an open-top London bus! Bonkers!), there are YouTube videos of Josh's utterly spontaneous and not-at-all-stage-managed musical quest. The group has its own song, which you're encouraged to perform and upload yourself, hastening humankind's slow cultural death in the process. The recurring melody sounds suspiciously like a seven-note ringtone, while the lyrics speak vaguely inclusion and connectivity – y'know, the sort of thing they guff on about in mobile phone ads. The third line is "I call up all of my friends". Why call anyone? You've got free texts for life, you prick.

It's so clumsily contrived it wouldn't fool a hen, yet we're meant to welcome this "supergroup" as an authentic grassroots musical phenomenon. On MySpace, Josh (or whoever's controlling him) claims, "It's a shame so many cynics think this band is completely manufactured."

So it's a genuine people's movement, then? And this band doesn't contain any paid-for session musicians? And that song wasn't written by professional tunesmiths-for-hire? And the lyrics weren't penned by some dickshoe at Saatchi & Saatchi? Hmm. Piss off, T-Mobile. Stop trying to "crowdsource". You're embarrassing yourselves. Scram. And empty that bucket on your way out.

Buy Charlie's new book The Hell Of It All for £8.99 (rrp £12.99). Visit guardianbooks.co.uk or call 0845-6064232