Cristian Crespo of Valley Village, California, said he found it ridiculous that automakers hadn't yet come up with a way to combine fuel efficiency with luxury provided by a SUV.

"It's not that Americans don't want to be environmentally friendly, it's just that we don't have much of a choice," he wrote. "As an SUV driver, telling me that my only alternative is a Toyota Prius or a Honda Civic is like telling me to eat beef jerky when I'm used to filet mignon."

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I think fuel is already a trivial part of the overall cost of an automobile. Considering the quote above it is probably quite reasonable to build SUVs out of expensive lightweight materials such as aluminum-magnesium and carbon composites, because people who buy them are willing to pay for luxury anyway. Reducing fuel consumption is just part of being fashionable for drivers of SUVs. They can handle the increased cost IMO.