Would you hire yourself in a customer service role (shop assistant, waiting staff etc), knowing what you're actually like as a person?
I wouldn't hire me. I have quite a lot of contempt for people generally and in past jobs it has shown on occasion (mostly in my facial expressions and general demeanour). Of course I was able to convince the interviewer that i'm a sunflower faced, docile idiot who enjoys serving the great unwashed, in order to get the job. All lies.