Perhaps, but I have no illusions they are working for me. They may be my agent in the transaction, but the check they take home on payday doesn't come from me. I know it, the salesman knows it.
Sure, they don't get paid if I don't buy, that's true, but their job is to often size me up so more operations in the car selling factory, like the F&I office can figure out if they can get even more from me.
I usually come in with a decent idea what I'm willing to pay and what cars are going for. I negotiate ONE number, the OTD figure at the bottom of the deal. If I have a trade, I make it clear that I am talking about the size of the check I write to take home the car today.
I come with financing already arranged if I need it, and if they want to try to get a better rate, I'm willing to entertain what they are offering.
I'm not interested in gap insurance, extended warranties, etc, as if the car isn't going to last 5 years or 125k miles, I should probably not be buying it.
If one has reasonable expectations and does a modest amount of homework, the experience is not horrible.