I agree totaly that a dealer could have modified a new car from how it came from the factory. That's not much different than having the 1st owner modify the car, or the first owner taking it to another shop to have the car modified. It would still be modified/customized, and not factory. The problem is that it can be very hard to determine when a modification was made and by who. Was it the dealer, 1st owner, 2nd owner, 2nd dealer when the car was traded in, 3rd owner, how do you decide where to draw the line? It's really a personal preference thing I guess.
I'm all for dealer installed options or other modifications if you can show reasonable evidence that they've been part of the car since early in its life. (I'm particularly fond of dealer installed underdash air conditioners, and hood tachs.)
I just can't bring myself to say that it's normal for cars to be different from how the factory made them because dealers modified them before the 1st sale of the car. Yes, it's very possible the dealer could have changed something to suit a customer, but if we're trying to draw the line between what is "correct" and what isn't, then "as delivered by the factory" is a very crisp line, while "as sold by the dealer" is a very blurry line.
