Don't see many Ferrari's, but I can tell you a Prius driver is almost certainly an asshole. They are either Top Gear driving or Hypermiling, either way its at least a nuisance and sometimes a menace.
from my anecdotal experience, it seems like the brand of car that assholes drive is determined mainly by the median income of the locale. in poor areas, assholes drive shitty old hondas. in rich areas, they drive bmws and mercedes. in california, you are quite right; they drive priuses.
I'm saying that there are assholes everywhere and they drive the car they can afford. the California part is kind of a joke, but also somewhat true in my experience.