In our society car salesmen have gotten a stereotypical bad rap. Unfortunately it seems that we assign the negative characteristics of 1 or 2 people that we meet in a particular line of work to everyone who does the same job. We do this with cops, lawyers, car salesmen, and others. Knowing in advance that you're in a line of work wherein your integrity gets questioned before you even introduce yourself to a customer has got to carry a lot of pressure.
The tipping point comes afterward.
If your customer sees that he can count on you to be honest with him/her as opposed to the 50 or 60 year old guy with the bouffant and all the bling he will feel safer in your presence. If, on the other hand, your customer sees that dealing with you is only to experience the stereotype that he was expecting from a salesman he will leave with that kind of chip on his shoulder and he will make sure that you share in it with him.
IMO, if you are sly people will be drawn to you initially because the lack of hair indicates that you have nothing to hide. And if you're not hiding yourself it indicates that you are more open and honest overall and not inclined to hide anything else, like the proverbial Car-Fax.
Of course, all this carries the weight of striving to do "the right thing" all the time and becoming conscious of the times when you are unsuccessful and making appropriate amends.