There are something like rule and setting that should be put over the playsyle of some player or their taste. If you want to play something so specific that is needed to change the whole game is better changing game or setting.

Example: i had created my own game and give it to my players to create their characters. One of them asked me to play a doctor who wants to cover his identity, i said sure, then he said and i want to be dressed like a medieval plague doctor, and i said no, if he want he could come up with some other mask or disguise, but in the setting there was no plague and that was not that kind of fashion. (I had included drawing and culture explanation in the game files)