Why I'm glad to be too old for ever-more costly stag dos: David Behrens

This cult of pre-marital bacchanalia has mushroomed since the last time I got hitched, when the stag party comprised half a dozen of us around a table in the local boozer, lamenting the days of women and song we had forsaken. Tetley’s must have been about £1.50 a pint then, so it came to less than 50 quid for the lot of us.

Today, a stag party means indoor skydiving, white water rafting or some other expensive diversion designed to take the groom’s mind off the decades fanning out before him.

But enthusiasm is apparently tailing off. The researchers reported that one guest in three typically declines their invitation because they’re worried about the cost – and why wouldn’t they be? Interest rates have rocketed to such an extent that newlyweds are spreading out their mortgages over 35 years instead of 25. And stocking the new house with food requires a loan in itself.

This should be an aberration, not the norm, yet Britain’s retailers are doing their best to convince us that we’ll have to get used to paying through the nose. Supermarkets in particular stand accused of forcing food prices to a record high in April and not always for reasons that are outside their control.

The Lib Dems are among those calling for the competition watchdog to investigate claims of excessive profiteering by the biggest grocers, with party leader Ed Davey suggesting they should be doing more to help shoppers struggling with rising prices.

He’s right – the Competitions and Markets Authority should intervene pronto, just as they did last month on fuel prices with the result that a litre of diesel on supermarket forecourts dropped by 7p, as if by magic.

Even that was a token gesture: since March diesel has cost less than petrol on the wholesale market yet garages continue to sell it at a premium. We overlook this sleight of hand because we presume, quite wrongly, that it’s just taxed at a higher rate.

In the food sections, the big supermarkets are using similar techniques to convince us that we’re getting better value for money than is really the case.

Tesco, for instance, is currently selling eight cans of Pepsi for just under £4 – but you can buy 16 cans for only £1 more if you have a Clubcard. You’re being encouraged to think you’re getting £3 off but you’re actually paying a 60 per cent surcharge if you don’t have their loyalty card. Doesn’t sound like such a good deal now, does it? For you or your teeth. Besides, why carry a loyalty card if that loyalty isn’t reciprocated?

It’s a common marketing tactic so is there anything wrong with it? After all, it’s always been cheaper to buy in bulk. I’d call it low level deception, on the scale of an illusionist who tells you he’s cut someone in half and then puts them back together. We’re just fools for believing him.

It’s no wonder that Aldi and Lidl are gaining so much traction. Both have now overtaken Morrisons, whose reputation for low prices has been consigned to fond memory. They have done this by telling the truth – or at least more of the truth – about how much the food costs to produce and distribute. They’re not ‘discounters’, as they are often labelled; it’s their bigger rivals who are inflators.

It’s no coincidence that Britain’s inflation rate this year will be the highest of all the G7 advanced economies – and that can’t be ascribed solely to Brexit, although it hasn’t helped.

It’s partly our own fault for letting ourselves be seduced by dubious offers and, as a result, becoming acclimatised to paying as much as sellers think they can get away with charging. They did it with diesel, backing down like naughty children when they were caught out, and they’re doing it with everything else.

If we’re told often enough that one type of fuel costs more than another, or that £800 is a normal sum for a weekend on the lash, we start to believe it – in spite of our better judgment. Have we lost our sense of perspective? As surely as beer is no longer £1.50 a pint.