The so-called "buff books" (traditional automotive glossy magazines) sell cars with sex appeal and fantasy. We all love to read about the latest exotic sports car or decadent luxury sedan. The magazines jockey for position atop the "road test methodology" food chain, by providing more performance stats, dimensions, and other objective data--if you measure more stuff than the other guy, you must have written a better review, right?
There is also a crucial need for glamor photography of the cars. They are (almost) always impeccably detailed, with rich glossy paint, upgraded interior options, and, whenever a driver is deliberately visible, they are either a supermodel or Marlboro Man type, wearing stylish sunglasses.
Why are these ingredients necessary? Because these unattainable cars are a fantasy and a fashion statement, far more than they are an interpretation of the need for vehicular transportation. Beyond basic day-to-day performance capabilities, safety features, and reasonable standards of comfort, none of the extra stuff is necessary. But it's delicious, and we love it.
I love fancy cars. I've bought and sold far too many cars over the years, much to the disdain of financial advisors and friends who just don't get it. Typically the process sees me get a bug to imagine what New Car X would be like to live with--both on the daily commute, and, when opportunity arises, on more fun trips. Sports cars provoke images of drives through empty country roads, luxury cruisers see me rolling into a big city and pulling up to a hotel valet, and trucks inevitably end up parked atop a remote mountain peak, disgorging camera equipment.
The practical reality, of course, is that most of us rarely have time to do any of those things. So we partake of the experiences vicariously, through glossy magazines, expensive brochures from the dealers, and, more recently, glorious interactive web sites and video. The community-building nature of online content means that we can develop virtual friendships with others who get to do the things we wish we could do with our cars, and see their photos after each trip.
The manufacturers also want to capture as many of these daydreams as possible. They don't want their offerings to be excluded as incompatible with any reasonable use a customer might pursue. This is why you see "Sport Packages" on cars (and trucks, and vans) with no authentic sporting pretense, or "Grand Touring" designations on vehicles no valet would ever leave right outside the hotel's front door.
But, as with all fashion, it's the idea of how these things make us look, flatter our egos, and otherwise enable us to participate in an alternate reality which is the fun of fancy cars. If sports cars were only sold to people who would use them to their full abilities, the manufacturers wouldn't be able to survive with such a small market. Purists decry the loss of traditional manual transmissions, but paddle-shifting automatics or dual-clutch arrangements serve the needs of a typical buyer much more, because they work in traffic, without wearing out your left leg.
So if the magazines are really fashion/lifestyle daydreams, what are they good for? Well, obviously, they do tests on normal cars as well. And they do provide some good information about critical flaws, real-world fuel economy, and the like. But you have to remember that they are not a substitute for you forming your own opinion--just because Brand X wins a comparison test doesn’t mean that Brands Y or Z wouldn't also suit your particular needs. The nice thing about competitive vehicle segments--family sedans, midsized crossovers, etc--is that none of them are fundamentally bad vehicles. Don't get hung up on comparing only those things which aren't subjective, like 0-60 mph times or "lateral/skidpad grip". None of those things tell you if the car will be good for you or not.