This question popped into my head while watching a string of old shows over the weekend: During the closing credits of a show, I have seen mentions of where a show was taped. On some shows, like those originating from Television City, an actual CBS logo with the "Television City" credit is included, while other shows (like some NBC shows) would mention studio locations in text only where the show was shot at "NBC Studios, Burbank", or "Sunset/Bronson Studios".
On the announcing side, nearly every game show taped at Beverly & Fairfax would also be mentioned by the announcer as "From Television City in Hollywood" as well either at the beginning or end of the show..
1) Is/Was it a requirement by some studios &/or networks that the taping location must be noted either verbally or in the credits?
2) Does/Did a studio location mention ever give the producer a discount of any sort for use of the studio?
3) Must a location be mentioned if a network's or studio's own crew members are used by a production company, as opposed to a production company using all their own "employees"?
I'm just curious as to why there is such a variance in the use of "studio credits" over the years?