It’s always a problem when one of literature’s big beasts wanders off the reservation into the badlands of genre. The latest to blunder through the electric barriers erected around the safe zone is two-time Booker prize nominee David Mitchell, whose new book Slade House is undeniably a haunted house story. Or, as the Chicago Tribune put it, his “take on a classic ghost story”. As if the thousands of genre ghost stories written every year by horror writers weren’t also one individual’s take on that classic form.

Slade House is a good ghost story, but is it quantifiably a higher form of fiction? Margaret Atwood’s dystopian masterpiece The Handmaid’s Tale certainly has fewer gunfights than Suzanne Collins’s The Hunger Games, but does that make it more or less realistic? I’m happy to call Doris Lessing’s Shikasta series far superior to Isaac Asimov’s stodgy Foundation novels, but thousands of sci-fi fans would disagree. And yet the literary world is determined to claim, even while it’s stealing genre’s clothes, that it somehow wears them better.

Glen Duncan, who writes books about fallen angels and werewolves, made it very clear that neither he nor Colson Whitehead were in any way genre writers, in his review of the latter’s Zone One, a book about zombies. Duncan seems to hate readers who confuse his books with genre fiction simply because he writes about lycanthropes. This is not unlike swearing at the world for calling you an Arsenal fan while chanting, “Ooh to be a gooner!”

As a brief glance at Amazon reveals, the world, its wife, their daughter, her mate Jenny and half the people you pass on the street are now “writers”. But literary authors aren’t self-publishing their books on Kindle. Quite the opposite. They have a swish sounding publisher. They write for the New Yorker or the Guardian. They’re overwhelmingly likely to have attended an elite university such as Oxford or Stamford. They have an MFA. It’s all indicative of one clear message: these people are smarter than you, so you should buy their book.

Literary authors are the luxury brands of the writing world, the Mercedes, the Harrods and the Luis Vuitton of high culture. Genre writers are mid-range consumer brands, with an equivalent status to Skoda, Argos and Primark. Stephen King is the Ford Mondeo of letters, the writer dads actually read while pretending they got past chapter three of Infinite Jest in their 20s.

Which is really the heart of the problem. The market for high-end literature isn’t a healthy one. Intellectuals are reliably penniless, and fancy reading habits don’t make you cool any longer. The people who actually buy books, in thumpingly large numbers, are genre readers. And they buy them because they love them. Writing a werewolf novel because you think it will sell, then patronising people who love werewolf novels, isn’t a smart marketing strategy – but it’s amazing how many smart writers are doing just this.

When I interviewed David Mitchell about his secret life as a geek, it was clear that the divide between literary genre fiction makes no more sense to him than the rest of us. In Mitchell’s words, “the novel’s the boss”, and arguments about marketing categories are not the writer’s concern. If the vast sea of authors competing for attention today want any chance of being as good as David Mitchell, they’d do well to follow his example and learn from both literary and genre fiction. They’re two halves of the same craft, and if the art of fiction is to remain healthy, we should stop narrowing its range with snobbery.