Because according to experts, in the modern world of art crime, you are more likely to be talking of characters such as the Dublin criminal Martin "The General" Cahill, or the purported UVF member "Half Track Mullan" than of aristocratic gentlemen thieves.
There are two common myths surrounding the art thief, says Charles Hill, former head of Scotland Yard's arts and antiques squad - that he is aristocratic, and that he is stealing to order for a "Dr No" figure, complete with secret hoard of priceless objets d'art. "They're not Raffles-type climbers with a box of chocolates. They're social climbing crooks. They're commodities criminals, whether it's drugs, securities or works of art.They start by stealing cars as teenagers, and then embark on their criminal career path."
He cites the example of Cahill, who graduated from domestic burglaries and stealing hire plant equipment, working towards his aim of becoming a major drug distributor. In May 1986 he organised a burglary at the home of Lord and Lady Beit, whose private art collection is considered to be one of the greatest of the 20th century. The paintings were to raise money for the drugs venture.
Cahill, who is described by Hill as "unsophisticated but cunning and persistent", used one of the paintings as collateral in a bank in Luxembourg. In 1993 he sent another to Istanbul in the care of a one-legged Scotsman known as Half Track Mullan, who was subsequently arrested attempting to swap it for heroin. Cahill was later shot dead by the IRA.
In the booming art theft industry, according to Hill, it is men like Cahill who are now the rule, rather than the exception. "Within their network the guy that steals the most valuable pictures is much more highly regarded than those who steal hub-caps. That's the pecking order of the criminal mind," Mr Hill says. "They do boast of what they've done to each other. It puts you above the guy who steals the JCB. It's straightforward one-upmanship out of Stephen Potter."
This is reiterated by Peter Scott, who was once known as "the human fly" as a result of his spectacular career as a cat burglar, during which he stole an estimated pounds 30m worth of paintings and jewellery. Mr Scott, a former public schoolboy who has stolen from, among others, Lauren Bacall, John Aspinall and Elizabeth Taylor, considers himself far removed from the perpetrators of petty or violent crime.
"I always had my own particular standards. I could hack stealing from the very rich ... but I couldn't be too happy on acts of violence or stealing property from people who couldn't afford it," he says. Stealing art, he feels, was different. It was a vocation that required intricate planning and knowledge. "I had a lot of passion for what I did. It was more important than anything, even more than my wives. It was the ultimate orgasm," says Mr Scott, who now works as a tennis coach.
He would watch four or five country houses, as well as a couple of town houses, at any one time. He also swotted up. "I know a bit about art. You do your research and eventually you know who has what. I would only really steal paintings when they were wanted by someone. Some paintings are a bit like currency. Hunting pictures and horse pictures by people like Stubbs or Ferneley are very popular." In fact, he said, they were so desirable to some members of the criminal fraternity that they would "take a chance" and hang their plunder on their own walls.
"I had a pal that did an armed robbery many years ago from a country house in Bristol. He put one of these paintings up on his wall. Twelve years later he had guests round to dinner that recognised it. He got seven years."
Mr Scott, who subsequently wrote a book about his experiences, was as famous during the Fifties for his social exploits as for his criminal ones. "The fact that I was a rampant cat burglar did attract some silly upper-class girls," he concedes. But he says he was never the Raffles character the newspapers of the time made him out to be. "I was in Groucho's last night with John McVicar and I said to him, you can start believing your own bullshit."
Mr Scott believes he may have been the last of a dying breed. "Not many people are prepared to go into a country house on their own," he says. It's all gangs now. Substances have become the easier way for young people to get rich."
The world of the gentleman thief has passed, he says, because of the increasing sophistication of security devices. "You can't really climb about on roofs and ledges today because of the cameras. You look at houses in The Boltons, Grosvenor Square, they're all camera'd up."
However, according to Colin Norvelle-Read of Trace magazine, a register of stolen art and antiquities, the new breed of art thief is matching those devices for ingenuity. The gentleman player is being replaced by the professional. He may not know about art, but he is well aware of the market and the "business opportunities" within it.
"The level of planning always surprises us. They go in there with little slide rules stuck up their sleeves. One chap went into a country house museum with a walking stick with notches in the side marking the centimetres, so he could note exactly where the infrared sensors were. We've even had people who wear socks which have stripes on for monitoring infrared sensors. "
The new breed of thief, he says, is more business oriented. "You might have people stealing to order. For instance the big business this year was garden statuary ... 17th-century urns, fountains - some of them are worth as much as pounds 10,000. Country house museums are now so tight with CCTV security that if [thieves] wanted to make money they had to adapt, to move location. So now they come into the garden with cranes."
In one recent unpublicised case, a museum that had installed pounds 300,000- worth of American infrared security equipment suffered a burglary after the thief shinned up a 50ft drainpipe covered with razor-wire. He simply wore kneepads, assuming, correctly, that no one would think to safeguard that window. "It's a terrible thing to say, but if someone really wants a particular piece there's not a lot you can do," says Mr Norvelle-Read.
The audacity of art thieves is still something that raises them a couple of notches above the procurer of drugs or stealer of hub-caps. Mr Norvelle- Read tells of one incident where a thief had walked around a stately home as a tourist and selected a picture with a large gilt frame of "something like a Gainsborough woman with a horse". The thief later returned and stole it, substituting a cheap poster copy of a woman and horse within a cheap gilt frame. Nobody noticed for several weeks.
"Bond Street is full of crooks," says Peter Scott. "It's littered with them." His tone is vaguely disapproving. Still, as with the best criminal logic, what goes around comes around, as he himself discovered last week. "Someone just stole the hub-caps from my Ford Ghia," he says. "I hope he's enjoying them."