Yes. Every group has one in order to promote and demote members.
Is the staff Super Admin in every group?


I think what he means is if a Chess.com STAFF member is a Super Admin of every group on this site.
If that is the question, no. Only officially run groups like the Official Chess.com/TV Group or Chess.com University would have a STAFF member as a Super Admin or co-Super Admin as in the TV Group's case. Whenever you see "Chess.com" as a prefix as the group name, you can be pretty sure a STAFF member runs it. But there are other groups, not entirely focused on Chess.com that might have STAFFrs as Super Admins. There are literally thousands of groups on this site and only 12-14 STAFFrs. No way could they run everything.
-Mark


Super Admins of groups don't have that many powers to be honest. They only have powers within their groups to Promote, Ban or Delete members, recruiting, match set ups and things like that. STAFFrs supercede all of that and can pretty much do anything and everything on this site you can think of when it comes to TOS. Super Admins control their own groups. STAFF controls everything.
-Mark
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