Actually, you could probably consider a GP a race car. They were run in Nascar for quite a few years.
But seriously, no one is claiming to have a race car/dd out of a GP. They are just like any other car, a car. People like to mod and make there car different from all of the others on the road. If you don't want to mod yours, fine. Personally, I think most Mitsu's are jokes. That is my opinion. If you don't want to see people mod GP's, don't spend time on a GP forum.