Large dealers will advertise a product for less than they pay for it. They call it a loss leader, which brings customers into their store/website. Then they can sell them additional products. Smaller dealers cannot do that so MAP is a way to try to stop that type of loss leader advertising and keep more dealers in the game. If we just permitted everyone to do as they wish, we would only have a few customers (Amazon, Walmart, etc.). This doesn't serve everyone.
Also, for many, low price is everything. They don't want the special service, or they will go to a store and take the special service (and not pay for it) and then go to the cheapest source for purchase. Some think that's smart shopping. The dealers providing the service they are giving but not getting paid for do not.
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