[JonW]

The price of the car has no bearing on the salesperson's commission. Most are paid on the profit off the sale, not the selling price. However, a dealer does get more holdback on a more expensive car. And if the car is selling at MSRP, there is a bit more profit in the extra options.

The big thing, as you say, is that it makes the ordering process and assembly line work easier, since there are not as many different variations. But if Mini Cooper can do it, why not Chrysler?