People hate car dealers for a reason. They are generally deceitful, money grubbing scum who conjure all kind of fees and charges, who "negotiate" merely to upsell customers with expensive upgrades, financing and insurance policies. And then when the car needs to be serviced they'll rape the customer again for the time & parts.
That isn't to say Tesla will solve all these problems (I'd be especially worried about the cost of servicing what's essentially a computer on wheels), but at least they charge a price and you know what you're getting. No negotiations. No oily salesman pitching stuff you don't need.