This year’s North American International Auto Show in Detroit featured fewer concept vehicles than past shows, and most of them were variations—some mild, some wild—of the standard sedan. There was only one truck-like concept vehicle, one SUV, and no minivans. There were also few futuristic-looking concept cars that might look at home in the Jetsons' garage. Instead, it looks like the auto companies want concepts they can quickly convert to showroom sales.