Definitions:
A free market is a market structure in which the distribution and costs of goods and services, along with the structure and hierarchy between capital and consumer goods, are coordinated by supply and demand unhindered by external regulation or control by government or monopolies.
Capitalism is an economic system characterized by private or corporate ownership of capital assets and goods. In a capitalist economy, investors are free to buy, sell, produce, and distribute goods and services with at most limited government control, at prices determined primarily by a competition for profit in a free market.
If Americans truly believe in free market capitalism, then it doesn't matter whether dealers would lose their jobs, or tax revenue would be lost, etc. As mynameisjim said, adapt or die.
iTunes brought about changes to the entire system of music distribution in the U.S. The record companies--after initial resistance--finally adapted.
The internet/iPad/Nook/Kindle brought about the demise of newspapers and bookstores. Many newspapers did not adapt or adapted too late, and died. Some bookstores did not adapt, and died.
This is how the US economy works--or how it should work. The threat of becoming obsolete is the very thing that spurs innovation.
No law stopped the internet from killing many newspapers. No law should stop Tesla from being able to sell directly to the consumer.
Look at it this way: Imagine being told that instead of buying groceries from your local grocery store, you were now required to buy your groceries from a designated "food provider" in your neighborhood. That "food provider" would buy the food from the grocery store, and then re-sell the food to you (after increasing the price to pay himself). Does that seem right to you? What value is the "food provider" adding to the process?