Discussion Main / FakeGuestStar

What about Glee? Characters such as Brittany (Heather Morris)and Santana(Naya Rivera) were marked as guest stars despite appearing in every episode, until Season 2 where they recieved regular billing.Matt (Dijon Talton) also received this treatment until he left the show at the end of Season 1. Even now, Mike Chang (Harry Shum Jr.), Lauren Zizes (Ashley Fink) and Sam (Chord Overstreet) receive guest star billing, despite appearing every episode, dating main characters, receiving solos, and major plotlines.

I was wicked here by the TNG Characters page, where several are described as being fake guest stars because it's a regular cast member playing a recurring or one-shot non-main character. Is that a different phenomenon? (one which is certainly common in animated shows)