I'd like to see someone try some clear acrylic rear fender/wheel skirts. Daimler has done them on a number of their efficient concept cars so as not to offend the "traditional" look.
Some manufacturers have done clear wheel discs as well, so you get the "look" of the alloys but a smooth surface.
Yes, they'll get dirty on the inside.
But I figure the guys for whom their cars' looks is a priority probably also spend more time on cleaning anyway.