It would seem natural to me that some groups would actually want their list to be scrambled, for example unlawful ones.
Others would want people to know where they are freely. For example police. They drive around in well recognizable cars and do regular patrols along the same routes, because the sense of security that this gives to people outweighs the advantages of being "undercover" and unpredictable.
I guess if you want to be this sort of undercover, you can freely do it by also using the tag on the right or not using one at all.
As long as everyone is allowed to do it if they want, its not really unfair. It only gets unfair if some are allowed to do it and others are not.
Either way, I see this as not a very big advantage.