While that is true to a point, unless everyone is driving around in exactly the same vehicle, it's almost impossible to really make things truly equal. The difference between a sub-compact car and even a typical midsize car (like a Toyota Camry) is huge, never mind between a sub-compact and a 6,000+lb truck or SUV.

Here's a neat video that demonstrates a crash between a compact car and a midsize car:

http://www.youtube.com/watch?v=vcTf78b8WfY

With that said....Presently, the #1 and #2 top selling vehicles in the world are the Ford F150 and the Chevrolet Silverado, both full size pickups. For the most part, it has been this way for a long time. Therefore, IMO, that is worth taking into consideration when deciding on a new vehicle to purchase.

I'd rather spend a few extra dollars on fuel a year than have to worry about the bumper of the most popular vehicles sold being aimed right at my head (with just a thin piece of glass to separate the two).