No, you are incorrect.
Back in the 80s my favorite channel was American Movie Classics (AMC to you young'uns). Back then all they did was show Classic movies, ad-free. The host, Bob Dorian, would usually lead in with some interesting behind-the-scenes story about the making of the movie, its stars, or sometimes about the time period when the film was made. They would sometimes have an intermission halfway through, where they might give you the schedule for when a particular movie was going to play during the week... or maybe they'd mention how it was Gary Cooper week and list all the movies they'd be showing. I suppose you could call those house ads - but that was the extent of their "advertising".
I still have several boxes containing VHS tapes that, at one time, contained ad-free movies I'd taped off of AMC.
Man, I loved that channel.