Sam and Friends was to the Muppets what the Cavern Club was to the Beatles.
Henson saw no need to erect a puppet theater in the studio…doing so would have been superfluous. The studio camera’s viewfinder defined the physical limits of a virtual puppet stage, Henson believed. Each television set receiving the signal at home, therefore, was its own theater.
Michael Davis, STREET GANG: The Complete History of Sesame Street (81).