I agree with you on that - but I’m a bit taken aback by the whole notion that a customer should negotiate based on the profit the business makes. To me, that’s simply not relevant.
Of course it is not relevant. Customers should negotiate based on what they value the purchase.
Dealers want you to dicker based on their mythical profit/loss on a vehicle. They are trying to make you sympathize with them, & make you think you are being unfair. You wouldn’t want to be unfair, would you?
If the dealership cannot make a profit, I could care less. That is not my responsibility. My only priority is the best vehicle at the lowest price.
At best, sticker prices, invoice games, & the like only give you a starting point in the negotiations. Research on the Internet is a much better way to prepare to deal.
My wife taught me this trick. It has saved me money & heartache over junk products. Read the reviews of a product, especially the negative reviews. Good reviews are often quite general, “Great product!”, & such, but bad reviews are more often very specific, alerting you to aspects of a product you may not like but wont find out about until after purchase.