With kusaba, the admin only can set the tripcode for himself and other admins, as far as I know. Correct me if I'm wrong, but either way, it's really nothing to worry about.
Also, by your logic, anyone who has a valid reason to use a tripcode should stay well away from Kusaba. Then again, maybe other board scripts have this ability and you just don't know? Best best would be to stay away form them all in that case.