I don't know the "marketing" thought process behind car color selections (Hell I have never understood anyone from "mahketing", ever!), other than that awful period in the 70's when everybody went "Earth Tones" and Porsche had some really bad color combinations that I would rather forget,
But people are, generally, I feel, afraid of "bold colors" on their 550/356 originals and replicas. Maybe the Emory boys are more daring, but there seems to be a slew of white/silver/red/black cars out there, and not much else. I've also noted that the West Coast cars seem to be more bold than those found elsewhere (and you guys/gals ROCK!)
Honestly, bucking the "factory-only" Porsche colors within the PCA takes a lot of guts, as people with too large bank accounts often have too large opinions to go with them, but what the heck do THEY know? I certainly didn't consult with them before painting my Pearl "Audi Pearlescent White" and didn't really care - I just thought it looked awesome! Never seen another one, although Marty's IM uses almost the same shade of Base Coat (I parked next to him once, and was tickled at how close they were.)
My mom was a teacher in elementary schools and everyone remembers her coral/white 2-tone '57 Ford Fairlane. No one remembers her all-white '60 Fairlane, nor her all-white '62 of the same model. All of her students remember her '64 Turquoise Galaxie XL Convertible, though, while totally forgetting her '66 and '68 Gold Galaxie convertibles.
Just goes to show that people like and remember bold colors, no matter the car model, and "Earth Tones" are, well, earthy. That bright Blue up above is in the Awesome category - Right up there with my Mom's Turquoise Convertible.
Go Bold or Go Home!