A mysterious contagion is blighting the planet; earth has fallen prey to zombies. Am I going to write a review of the $200 million Hollywood blockbuster World War Z? No: I’m commenting on the Tour de France, which starts for the 100th time on Saturday, June 29.

Cyclists now resemble the undead against whom Brad Pitt battles in the film. Doped-up automata, unresponsive to their surroundings, they are like corpses controlled by chemists. At least that’s what our media would have us believe.

Cyclists have always taken dope. When the Tour first started in 1903, strychnine and cocaine were the drugs of choice. By the late 1950s, synthetic stimulants, especially amphetamines, were regularly used to sustain competitors through 23 days of the most exacting physical demands. Jacques Anquetil (1934-87), who won the Tour five times, spoke openly about how cyclists didn’t opt to use drugs: they just couldn’t do without them. No one cared. Only after Britain’s Tommy Simpson died during the 1967 Tour, did cycling – indeed, sport generally – begin to wonder whether competitors needed protecting from themselves. Anti-doping rules were introduced in the early 1970s, but have had little effect in cycling.

Last year, during his confessional interview with Oprah Winfrey, Lance Armstrong was asked if doping was part of the process required to win the Tour. He answered: “That’s like saying we have to have air in our tyres or water in our bottles. It was part of the job.”

If Armstrong is to be believed, drug taking in cycling is not seen as a transgression: it is normal behaviour. Armstrong was a scapegoat: someone blamed for the wrongdoings of others, especially for reasons of expediency. It made more sense to hang the most famous cyclist in history out to dry rather than examine the entire culture of the sport. Armstrong merely confirmed what most people have known, or at least strongly suspected for years. Cycling is a sport in which doping is an everyday practice.

Here’s my question: do we care? The media tell us we do, or, if not, we certainly should. The media themselves care: they have turned Armstrong from one of the greatest heroes in world sport to the biggest cheat in history. I’m not sure the rest of us feel the same way. Some years ago, I was involved in a round table radio discussion in which one of the discussants suggested that we should stage two Tours de France: one for riders who used dope, the other for those who chose to compete au naturel. “It’s possible,” I replied. “But who’d watch the clean Tour?” We’ve all become used to athletes pushing themselves towards and, occasionally, beyond the limits of the human body. We love intense, unbridled competition. Sport conceals its own preparation: we won’t see the riders taking drugs, yet we’ll know they are using something; and we will enjoy the competition just the same. People like eggs for breakfast; they don’t need to see chickens that produced them fed.

If consumers were so turned off by cycling’s close association with drugs, the Tour wouldn’t have lasted long after 1973 when the first authentic tests revealed the widespread use of drugs by riders. Since then, a steady crescendo has built, every Tour yielding cases of doping. The 1998 Tour was so affected by doping that it was known as Tour du Dopage. And yet the race continued to grow in popularity. In terms of live spectators, the Tour is the biggest sports event in the world – by some margin: over 12 million people throng the streets over the period of the race. The Tour is only thinly popular outside Europe, but an estimated 2.5 billion people are exposed to it, counting those who read about it in newspapers. Television corporations pay about $200 million per tour to the organizers. Sponsorship deals are valued in dozens of millions.

Despite Armstrong’s evidence about the ubiquity of drugs in cycling, despite 2006 winner Floyd Landis’s claim that the cycling’s corrupt governance has created an environment where cheating is required, and despite last week’s admission by Jan Ullrich, who won the Tour in 1997 that “almost everybody back then took performance-enhancing substances,” enthusiasm for this year’s Tour will be undimmed.

There is a disconnect between how the media reacts to doping in sport and how fans think and feel. Consumers don’t share the delirium that follows a positive test. We have doubts, but they rarely interfere with the satisfaction we take from the Tour. In common with all other athletes, cyclists are not there to provide decency, moral direction or lessons in propriety; they are not supposed to be paragons of rectitude whose most iniquitous habit is an occasional e-cigarette. They are supposed to send a sudden, strong feeling of excitement or exhilaration through us. When they do, they solicit our approval. We’re not in denial: we know they will probably be using dope. Sport is a world long since purged of goodness.