Well there is a certain commander that is infamous for ramming players in stations. If he could change his name at will it would be easier to catch commanders unaware. And he could hide from players wanting revenge.
For other players, a new commander name must be accompanied by a list of old names of this commander. Some players have personnal accounts to settle with other commanders ...
Thanks for the answers.
A list with aliases the CMDR has used in the past is a nice idea. I think that would add to the game play.