Because the rest of them look like what Steve Buscemi would look like in automotive form.
We know that you've probably already seen several hydrogen cars coming from the L.A. Auto Show, and it's even possible that you're thinking that this is essentially the same thing on an A7 body. Well, that would be incredibly boring, and the A7 Sportback H-Tron Quattro is thankfully a lot more interesting than that. The car is actually a plug-in hybrid, but in the place of the usual gasoline range extender, there's hydrogen fuel cells.
This is actually a pretty interesting idea. Not only does it mean that the car can go further on a tank of fuel (never a bad thing when hydrogen fuel stations are still so rare), but it ultimately makes for a more simplified drivetrain, for a plug-in hybrid. The electric motor would simply switch from drawing power from the battery to drawing power from the fuel cell. That means the vehicle is also fairly light for a plug-in. In fact, at 4,300lbs, it's only 100lbs heavier than the standard gasoline A7. Audi certainly didn't invent either the plug-in hybrid or the hydrogen fuel cell car, but it's an interesting idea that we'd be curious to see more of.