The buyers of these cars do not care. It's also cake for someone spending $100k+ on a ridiculous sports car to put in better seats if they choose (something that is a very personal choice based on your size and preferences). Ditto the shifter and pedals. The materials for the door panels/dash/etc are utterly meaningless to most of those buyers as well. Cost is an issue. That's why the R8 costs way more than the GT-R, even when the GT-R keeps up with it (even dominates it in many/most areas). Higher cost of materials and construction. End of the day, pick what you want. Sales of Vettes are huge because it's a performance monster for the price, and is simple to add power to while still remaining reliable and efficient for what it is.