And they think watching United is becoming gentrified. Nowhere is there such a concentration of fur coats per head of population (at 27,000 just about half the capacity of Old Trafford). Nowhere, too, is the experience of watching professional football quite so luxurious or unusual, even bizarre.
You have to take a lift or escalator up to pitch level, with sports halls and conference rooms occupying the first two floors. Up there, within the beige Provencale stonework, there are only 15,000 seats, in tasteful complementing yellow, which Monaco will fill for United, thanks in part to 3,000 visiting fans, but rarely do otherwise.
For the "club privilege" on the half-way line by the VIP area there are little red and white-halved seat covers, but then all of it seems privileged. In a press room resembling the bar of a London theatre, they serve Moet and Chandon along with the crudites. At one end of the stadium - it might be called the Ramada Hotel End - the M-shaped arches evoke a gladiatorial arena rather than McDonalds, although there is one nearby in those Terrasses de Fontvielle and Quentin Tarantino was almost right in Pulp Fiction. You can indeed get a "Royal Cheese" (not Royale with Cheese) rather than a quarter-pounder, because of the metric system and not in deference to the ruling Grimaldi family.
The stadium is all architecturally impressive, with a distinctiveness and sympathy for its environment. It can also feel quite soulless, which has much to do with the opulent Monegasque community itself. The night I went, Association Sportive de Monaco were playing a League Cup tie against Second Division Niort. The crowd was estimated optimistically at 1,000, and when the thoroughbred home team lost on penalties, you could have heard a jaw drop. "Ultras Monaco" said a lone banner and you wondered where they got the plural from.
"After Celtic, it's very strange," says the Monaco and Scotland midfield player John Collins, who was made captain that night against Niort in the absence of the goalkeeper Pierre Barthez. "You can't pay people to come to the stadium. You can't buy passion. You look forward to the European nights here. I definitely play better and I think the team does too when there's pressure on them. Quite often you find it affects the bigger clubs who come here more. We are used to it." Many tax-break residents, it seems, are away in mid-winter.
Professionals, Collins points out, should be able to motivate themselves but he admits it can be difficult. "In certain matches the level of the team can drop. Against the smaller teams, sometimes some of the players may not fancy it. You wouldn't get that in Scotland because you would have the crowd on your backs."
Actually, they can get the crowd on their backs here - as everywhere - but the shouts are often isolated. Some players shrug them off, some take them to heart, says Collins because, embarrassingly, you can hear every word. "It's a different game here, more like chess sometimes, and French supporters are different. There's less passion." Collins agrees with Michel Platini's old saying that France has spectators rather than fans.
In such an atmosphere, the game can be slow, he acknowledges. "It can be flat as well and what with the running track and the ball going into empty seats, it can take some time to get the ball back into play. As a result players can take their time with free-kicks and throw-ins and it's something we have to work on, to keep the tempo going."
That Monaco survive and indeed prosper by attracting some of the best players in the world such as Glenn Hoddle, Jurgen Klinsmann and George Weah - for a couple of seasons, at least, before the low-key atmosphere gets to them and they move to bigger pastures - is down to a mixture of the lifestyle and the wages the club can pay thanks to the patronage of Prince Rainier. While the club's French players live outside the Principality and pay tax at 55 per cent, the etrangers can live in luxury club apartments unburdened by tax.
Collins dispels any thoughts that la vie douce makes Monaco a soft touch. "The place is laid back but the football club is not," he insists as we sit sipping coffee and mineral water in the American Bar at the magnificent Hotel de Paris opposite the Casino. "The president and the coach [Jean Tigana, fixture of the Platini-led midfield in France's 1984 European Championship-winning team] are desperate to win.
"Everything is very professional, very thorough," Collins adds. "I know a lot about United because I have Sky here but by the time we play them, we will all know everything. We will have a video session in a conference room at the stadium, with all their corner and free-kick routines edited on to one tape."
No wonder Arsene Wenger prospered here before becoming coach of Arsenal. "It's also very scientific in terms of conditioning and diet," adds Collins. "The players are fitter, leaner. We stay in hotels before every game, home and away and we can be away for nine-day training camps pre-season and in the midwinter break. It's three sessions a day, up at 6.30am. The life is fantastic here but the training is hard."
The first few months were the hardest, he says, as he and his wife and two children settled. He also had to endure a French teacher following him everywhere all day to accelerate his learning of the language but you get used to it all, he says, even all the pasta with no sauce, just cheese. Yes, he does pine for a fry-up now and then.
One area, Collins believes, where the club could be more professional is in the quality of the surface on which the team have to perform. "The pitch doesn't help us," he says. "Because it's built high up, there is not that much earth underneath, so the water just stays there when it rains. When it's sunny, it just dries out, making it bumpy. I keep speaking to the manager about it but nothing seems to get done."
So there you have it: Monaco, the club that seems to have everything. Apart from fans and a good pitch, that is.
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