Created by credits

On a related note, I've been confused as to why adding "created by" to someone's writing credits apparently triggers an additional, superfluous "(creator)" credit. Look at Matt Groening's page, for example: https://www.imdb.com/name/nm0004981 All of the credits for his shows read "created by, developed by (creator)". Yet when you try to edit them, it turns out "creator" isn't an editable attribute. So it's apparently an automatic addition, but it's completely redundant.