In many periods in human history, people have no choice in this kind of thing. The class system is not very mobile and there is no mobility between them. And you could be borne into a place where you have limited or no choices for example if your dad is an executioner? You're doing for a living. In all probability, you're going to be executing people too. This is why authorities and the citizens want the executioner dressed all times in clothing that clearly marks out the fact they're the executioner. It's so that the crowd knows, wait a minute, there's the guy who tortures and kills and if i touch him even by accident, i'm dishonored