I have to say that the "extended leather" in my car is nice but really is 1/2mm thick leather glued to a plastic substrate. Having dismantled the dash, it is really hard to see how they justify the price of stuff. I think a lot of it is simply what they believe the market will bear. I have little doubt that the same applies to other manufacturers as well.
Regarding wheels, for instance, there is no structural or materials difference between the available wheel styles, but of course the price differences are astronomical. There is no material justification for the price of the turbine wheel vs the "standard" wheel. There may be some difference in tyres, but even there, one has to question how some of the astronomical prices are justified.