I embraced color retention on the R8's sideblades and used complementary body colors, I particularly like Suzukagrau Metallic / Brilliantrot and Daytonagrau Perleffekt / Ibisweiß. (Note: Suzukagrau Metallic is only available when purchasing the Audi R8 LMS Race Car '09 in that color--a 1,350,000cr nab.) Just be sure to buy the car with the sideblade color you want to keep, as it cannot be changed. It's also worth noting that the Carbon Sigma secondary available on the 4.2 model has a visible carbon fiber weave that matches that of the optional natural finish carbon fiber hood--but sadly it's only the center section of the hood that changes.
No telling why it was done this way but it is what it is.