[1] The punch line is known for its use as a basic sociological and psychological experiment, specifically relating to mob mentality and the pressure to conform.
The basic setup is similar to the Asch conformity experiments, in which people showed a proclivity to agree with a group despite their own judgments.
[3] However, the phrase itself was being employed in an absurd and humorous context as early as the 1750s, when it appeared in a well-known piece of literary nonsense by English dramatist and actor Samuel Foote in order to test the memory of a rival: "So she went into the garden to cut a cabbage-leaf to make an apple-pie; and at the same time a great she-bear, coming up the street, pops its head into the shop.
It has been used as the name for rock bands, as well as a short-lived TV sketch comedy show (No Soap, Radio) starring Steve Guttenberg that aired on ABC in spring 1982.
"[8] In "Pie-O-My", the fifth episode of the fourth season of The Sopranos, the name of the band playing at The Crazy Horse is No Soap Radio.
In "Brain Scramblies", the third episode of the second season of What We Do in the Shadows (TV series), the vampires' human neighbor Sean exclaims "No soap, Radio!"