It was Napoleon who once called us a "nation of shopkeepers". To judge from the reaction to Antony Worrall Thompson's pilfering from Tesco, we are actually a nation of shoplifters. Still, celebrity shoplifting is a source of hilarity, not outrage.

We don't know why Thompson stole nasty coleslaw when he was buying nearly £200 worth of champagne. We don't know why Tesco watched him do this five times. The man is a mystery. Even to himself. Since being caught stealing, he says, he sobs himself to sleep. He has floated all kinds of deep-rooted psychological difficulties from childhood abuse, to the collapse of his business, to anaemia, to bereavements or even wondering if he has Alzheimer's. He is now going to get the treatment he needs. It's a shame we don't have Shoplifters Anonymous as they do in the US. Celebrity shoplifting is seen as a cry for help. Embarrassing, yes. Evil, no. Remember the "Free Winona" T-shirts?

Such people don't steal because they need stuff or are immoral. They steal because they are stressed/addicted to painkillers/have a deep-seated need for love. I get that. I have a deep-seated need for love but I don't often wander around Tesco looking for it.

Part of our understanding reaction comes from the fact that we are more sympathetic to crimes we may ourselves have committed. Obviously, my friends and I were never tempted to shoplift even though our anarchist texts told us it was a good way to "poke a finger in the eye of big business". Consumer lust was a bad thing but what if you shared the proceeds? On those terms, it would have been immoral to steal from little shops, of course, but not big bad superstores. Stealing from them is victimless crime – not like burglary or mugging.

But the crime I am talking about is amateur shoplifting. The type that I, as a middle-aged woman, could find myself doing owing to my "midlife crisis". There are whole studies on "Nice Women Who Steal". It's a cheap thrill. Well, free, actually. There is a lot of "I don't know what came over me" post-crime, and some connect shoplifting to an Obsessive Compulsive Disorder with a purge/binge element coming in the form of risk/reward. Kleptomania, of course, was once explained by the "wandering womb" theory. Literally, women were thought so peculiar that we must have wombs where our brains should be. Use that one next time you find yourself in Waitrose stuffing high-end deli items into your knickers.

Actually, this pathologising of deviant individuals masks the scale of the problem. There is a massive amount of professional shoplifting and the cost of it is paid by the consumer, often in the form of deeply unimaginative crime prevention. What was Tesco doing watching CCTV four times before they nabbed Thompson? Professional thieves know how to get around most tagging and alarm systems. Ever since goods have been put on display instead of behind counters, so we can touch and feel them, shoplifting has gone up and the shops underwrite the price.

All crime is opportunistic and shoplifting depends on perceived risk. Some shops look to me as if they are asking for it, even though I am not a criminal. Or stressed. Innovative crime prevention strategies are coming out of places such as Design Against Crime (DAC), a research centre at Central St Martins, run by Professor Lorraine Gamman, which asks retailers to "think thief" and understand what "the criminal gaze" sees.

That means seeing what is easy to swipe. Thompson was caught at a self-scanning till. Big supermarkets are reluctant to say how much they are losing with them. They simply say that self-service tills enable them to cut jobs and that some customers love them. Especially those who buy "embarrassing items". I guess this means condoms and tampons, not Fray Bentos pies. Personally, these machines drive me insane and I always need to call for help.

Somehow, though, service has come to mean a Mary Portas type of middle-class obsession. Really, service for many just means some human interaction. Supermarkets are the only places some people get it. Would we be less likely to steal while chatting to someone? Or in a recession do we expect more theft?

All post-riot analysis was keen to make a distinction between looting (criminal and damaging) and shoplifting. Yes, we know that there were many stupid acts of defective consumerism. Yes, small, local shops were wrecked as well as big chains. But the sentencing of some who wandered into already vandalised shops and took something in a Worrall Thompson-type moment of madness seems disproportionate. We care little about the traumatic childhoods of those people, or "the stressors" that caused the shoplifters of the world to unite. Custodial sentences, not treatment, have been given and largely backed by the public.

Perhaps, though, random acts of stealing such as Worrall Thompson's, of taking because we feel taken from, make us question some of the basics. There is a free market in morals here. There are fine lines between deviance, desire, debt and duty. The barcodes on these items are not always so easy to identify.

This is how daylight robbery happens. Not in a riot, or a revolution. It's a mistake! It's the menopause! For look here, I am the consumer but doing the work of the cashier. Everything is at my fingertips … until I hear the demon robot voice in the machine. I ring the bell for assistance while it taunts "Unauthorised item in the bagging area". And there always is. And it's not just me.

Shoplifters Say They Steal Because They Need Love. I Need Love Too, But I Don't Wander Around Tesco Looking For It