Not necessarily. "Hancock's Half Hour" and "Goon show" episodes were sold on vinyl records at the time (and are still to be found on the big internet retailer on Vinyl, CD and MP3).
If the media were in the house, years later, kids would play them for amusement.
:)
the only time I've ever heard the Goon show or Hancock's Half Hour, has always been whilst listening to the radio (typically 2 or 4) that makes a reference to the shows and plays a few seconds clip
Within my limited field of family and friends I would say that people have heard about them, but have not really listened to them
The funniest one I remember is "The Blood Doner", which turns out was a TV episode (most were just radio).
"The Radio Ham" is also good.
[1] https://en.wikipedia.org/wiki/The_Blood_Donor / https://www.youtube.com/watch?v=dEUvyaNu0uw