I've often been amazed the car-dealer industry has lasted this long. It's all too often based on deception, disrespect, intimidation, and rip-offs - from the showroom (overcharge as much as possible), to the trade-in aspect (under-charge using the same tricks ... go figure) to the financing (bury the overcharging in extra years of interest paid), to the garage (a skilled mechanic will often still charge far less than the dealership for the same service).
No, not every dealer works this way. Just the majority. If Tesla can make a change to this phenomenon, then good riddance to bad rubbish.
As an aside, this (long) story from Edmunds gives outstanding insights to how dealerships work, and what options are available to consumers.
http://www.edmunds.com/car-buying/confessions-of-a-car-sales...
It's fascinating to see how racial profiling comes into the mix. An ethnic group - according to dealers - will be known to have bad credit, or to pay the overcharged price no matter what without a fight, or (as dealers claim of white people) chiefly car-shop online and come armed with information looking for the best price.