The test drive part is a main consideration. Love the idea, perhaps it is more of the AAP parts buying model, buy online and have shipped to a b&m store or buy their wares off the shelf directly.
But one cannot underestimate the power of the test drive and shopping for cars.
What this may do in the paradigm is allow smaller, more streamlined dealerships who don't have to sit on as much inventory.
At the same time, aim sure the OP haggles over his real estate deals, so not sure why this is any different. Mir anything, many supposedly prefer the android model as some vendors will offer them at a discount so they feel that they are getting a deal.
The other side of the coin is how many warranty issues have already existed, whee dealers don't want to honor, and what will happen if all margin is taken out by online sales. Will some dealers give the online buyers poorer service?
Huge possibilities here, interesting to see how/if it unfolds.