They have to drive new Porsches all the time (the showroom and service area aren't on the same lot), so one would assume dealer prep for a new car would mean driving it between the two places.
That's different than say 10 miles to blue's house. And they own the new Porsches, that's different insurance, I would think.
They have to insure someone to drive other people's porsche's presumably all around the DC area. Wow. Isn't there a Naughty By Nature song about that?