There is also the case of the
Goddess of The Manifold whose presence was minimal; in such cases it is the validity of
statements that matter.
On the background characters, I think it was later clarified in CRT for characters like human like with 10-B statistics without special abilities, feat or powers; but if the characters have similar statistisc however with should have notable powers, feats or statistics like impressive intelligence, the page creation was fine in most cases (DC and Marvel might have their own rules was based on minimum issue appearance); there was a time when such non-notable pages used to allowable, usually focusing in series like sitcom.