Ronnie Barker started in Rep.
He always said it was great training for when he had to play so many different parts in TV shows (like the Two Ronnies).
Basically you were doing one show that week, rehearsing for NEXT weeks show, AND buying props and doing the scenery for the show the week after.
And you had to play so many characters such as vicars, criminals, majors, policemen, posh people, working class people etc etc
Rep was very popular in the 1950s when few people had TV and they would go out to see a show at the local rep.
Barker said on some shows (Friday nights?) people would bring in fish and chips and eat it while watchng the show. You would get the rustle of the paper during the performance.
Often the same poeple came to the theatre week after week and they got to know the local actors who became "stars" in their local area.