So if "anything that gets you to the executed contract is part of the sale", shouldn't all those independent car dealerships be paying the car manufacturers for those expensive and slick TV, magazine and internet advertisements they produce to get people to go to said dealerships to buy their cars?
Actually, we do. If you look closely you'll often see a line item on the final invoice for something like "advertising" or "promotion". Yup --- they make you pay for the advertising.
I learned this years ago from a site that walked through car purchase negotiation techniques. Sorry, I don't remember which site.
(Or do they already?)..