Having been something of a European institution for years, the end of duty-free, the lowering of some Nordic duty rates and cheaper prices in domestic supermarkets have combined to reduce the allure of the booze cruise. Chris Losh reflects on the dwindling popularity of this European tradition.

Summer's here - and never mind dancing in the street, half of northern Europe, at least, has usually been content to spend it rolling in the aisles, thanks to mountains of cheap booze, bought on the various ferries.

But for how much longer, I wonder? Could the sight of frantic shoppers piling cases and cases of super-cheap plonk into the back of groaning Mondeos be one of those images about to be consigned to history, like Pathe newsreels of people smoking in cinemas? Will we look back in 20 years and think 'I can't believe people ever did that'?

Certainly the cross-channel ferry business has taken a real battering of late. A combination of strikes, berthing problems at Calais, and competition from budget airlines (which has contributed to P&O's decision to abandon all sailings from Portsmouth, for instance) has seriously hit passenger numbers, and with them sales of French-duty-rated booze.

Some of the problems have been resolved, and sales have recovered slightly as a result, but booze cruising was generally in decline, and consumer interest may well never return to the level it once was. Once one-time bargain hunters have discovered that they can live without cheap booze - or, perhaps more likely, that their local supermarket is offering promotional deals that are almost as good as those in Calais hypermarkets - it's unlikely that all of these bargain-seekers will return. Especially since the thought of a four-hour ferry crossing and a 12-hour drive to get to a holiday destination is increasingly being replaced by a two-hour flight and a rental car at the other end for the same cost.

It doesn't look a whole lot better in the Nordic region either, which has always been a huge market for booze on the ferries. Some of it is bought at lower duties,  some of it is duty-free, with ferries berthing for an hour at the tiny island of Öland.

Although it belongs to Finland, Öland is officially not part of the EU thanks to a quite spectacular bureaucratic oversight. And with its booming duty-free business, the EU is terrified of the amount of subsidy it would have to shell out to support the place, should it close the loophole. This provides a convenient loop-hole for Finns and Swedes who are enthusiastic about loading up with Absolut and Gallo. Theoretically, of course, there are limits, but one seasoned travel retail observer described them in this particular case as 'existing in principle, but not in practice.'

For those who want huge volumes legally, of course, there's always the chance of a voyage to Estonia, now part of the EU and with far lower duty rates. A Volvo hatchback can hold an awful lot of vodka, scotch and bag-in-box wine, certainly more than enough to cover the price of the ferry ticket…

But even with the Tallinn run's growing popularity, this is not the market it once was. A couple of years back, Finland and Denmark both cut their duty rates, which led to an almost instantaneous fall in booze sales within Sweden as Finns stopped popping over the border to buy their hooch and Swedes in the south of the country carried out a booze-migration to Denmark.

Now, strong rumours persist that the Swedes are about to lower their duty across the board and if the various Nordic duty rates come more or less into line, the big sufferers are sure to be the ferry lines, as the once-strong imperative that drove Nordic populations on to boats in search of bargains is removed. Ferry operators are already squeezing margins to the bone in order to offer deals good enough to entice passengers on, and it's hard to see how much lower they can go, without turning, effectively, into floating supermarkets with enormous overheads.

Drinks do have a future on the high seas, at least in the short term. But a few years down the line I can't see it being at the pile it high, sell it cheap level. The question is, how long can the ferry operators leave it before re-inventing themselves?