Who with a conscience could glug back a bottle of Fiji mineral water? Shipping H2O a gazillion ungreen miles “from an artesian aquifer at the very edge of a primitive rainforest” to a British home blessed with sanitary tap water - a facility lacked by a third of Fijians - “borders on being morally unacceptable”, says the Environment Minister, Phil Woolas. Cross it off the shopping list then, with the “cruel” eggs and “unhappy” chickens, those aerosol deodorants and poor, tormented veal escalopes.

Who can be in doubt that our every consumer decision is a moral question. No excuses accepted. Even a single mother who was merely guilty of feeding her children cheap protein can be harangued on national television by an Eton-educated chef for supporting the abuse of domestic fowl. Crack-smoking hookers with their raddled complexions, tarty clobber and children in care are not as heart-breakingly cutesy as baby piggies peeping through crates, drowning polar bears, or even chickens. But surely we can find an ethical champion in the wake of the Ipswich murders to tell men not to spend their money on prostitutes?

Steve Wright's murder of five young women has at least clarified the bleak economics of such transactions, that men who buy street sex are fuelling a life-leeching drug dependency, isolating the vulnerable from loved ones who might save them, making them 18 times more likley to end up asphyxiated and naked in a shallow ditch. And these Ipswich women were at least streetwalkers.

You might think having sex with Wright on his bedroom floor, because he always got cramp doing it in his car but feared his girlfriend would smell you on his sheets, is degrading enough. But at least these women were not pimped, imprisoned and abused in flourishing suburban brothels (would “battery sex farms” arouse more fellow feeling?), whose proliferation astonishes even the police - 80 discovered in Cambridgeshire last year alone - set up by entrepreneurial traffickers to feed an upsurge in demand.

Yes, Whorehouses UK Ltd is doing a cracking trade. Punters have doubled in a decade: now one in ten British men has visited a prostitute. And really why not, when even glossier men's magazines give the message that vice is nice, advise how stag weekenders can buy firm young booty in Tallinn or Budapest, when lap-dancing clubs are mainstream fun - from “private dance” to upstairs shag being a blurry line - when omnipresent internet porn feeds a sense of male entitlement to every unfettered whim. Now the sex trade has rebranded itself a wing of the leisure industry, moral disapproval has evaporated and men can concentrate on getting value for money with websites like punternet.com on hand to assist.

An average massage parlour visit costs £126, although Wright, after a lifetime of haggling with whores, always paid below the going rate. He stopped visiting private saunas because they charged him £65; the street girls would ask only £45, but he'd always drive them down “to what I had to spend” and in their addiction and desperation they'd do it for 20. “You get two girls for the price of one,” he boasted in court. That mum buying two-for-a-fiver Tesco birds was more contrite.

But just as Hugh Fearnley-Whearnley breeds “happy chickens” who skip through wooded glades, we are told by those (mostly men) who fear a Swedish-style criminalisation of punters, that there are many prostitutes, neither coerced nor addicted, who relish their chosen profession. “Happy hookers”: that hoary old male fantasy of women who get pleasure, even multi-orgasmic joy if you believe the deluded fools on punternet, from being paid for sex is periodically fed by fictional callgirls, most recently Billie Piper in Belle de Jour, with her classy clients and La Perla undies.

But this horny imagining clashes with the reality of a trade that 89 per cent dream of escaping. And indeed schemes to assist prostitutes getting off the game - and the drugs - have many takers. If the Ipswich one hadn't needed five deaths to get proper funding maybe Tania Nicol could have made it as a hairdresser, Annette Nicholls as a beautician. As Paula Clennell's sister put it: “The life she put up with is completely different to the life she wanted.”

The happy-hooker brigade extol the shop windows of Amsterdam, the legalised brothels of Nevada as gleaming examples of where sex for money, if transacted honestly and hygienically, can be an equable exchange. Yet neither hold up to close inspection: the Dutch are currently rethinking their red light districts since they are magnets for organised crime, drug dealers and traffickers. And legalised brothels, according to a recent two-year study, keep women in social isolation, often in cruel and inescapable conditions: “pussy penitentiaries” one Nevada inmate called them.

But men who use prostitutes need the happy hooker. Those with a semblance of a conscience seek reassurance that buying their jollies is hurting no one. The happy hooker, like the happy chicken, can be consumed without guilt. Others, like Wright, muddled and damaged by a rackety, violent childhood, perhaps need to believe they are wanted for more than their money.

In a TV film by Alan Whicker about Thailand's island brothel Pattaya, a 25-year-old Wright can be seen embraced by an exquisite teenage prostitute, whose gaze he holds with proprietorial pride. Throughout an adult life of disastrous relationships, including two short marriages, Wright would head back East whenever he was flush, to treat himself to an ego-healing session of “me love you long time”. For the emotionally stunted, perplexed by the complex and contradictory demands of real women, the dreary compromises of human relations, prostitution is blissfully simple. You know what she wants and once you hand it over, you get what you want, no snidey remarks, no questions asked.

While the Government is right to evaluate further whether the Swedish model leads to a true reduction of prostitution, or whether it is driven into deeper, more dangerous, places, one thing is certainly true: criminalising the buying of sex at least states categorically that it is not normal or acceptable, but, since it is incompatible with human dignity, morally wrong. And that is what we need to tell our young men but never do. Why are we hand-wringing moral relativists about women but not chickens? Why, at the very least, are punters not branded the most unethical consumers of all?

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