While checking the list of moderators on a main site, I'm surprised to find the name of a staff member! Yes, Marc Gravell is appearing on all sites.
Here is a screenshot of
/users?tab=moderators page of the site where I have a mod appointment:
You can take a look at that page
https://<anysite>.stackexchange.com/users?tab=moderators on any site to check.
I have also tried https://stackexchange.com/about/moderators out of curiosity:
Thinking that this might be a feature-update, I have checked MSE and found that Thank you, Marc Gravell! is leaving the company.
So, I assume this to be some bug or...<reading title of this question> :)
Note: Community moderators can also find him on /admin dash board with the comment "Moderator has not accepted the agreement".