I don't think that much changed by 1980. A VCR was still a rare item at that point and the catalog of films was tiny. I doubt even 1-2% of the US/UK had a VCR at that point.
VCR revolution doesn't really set in until about 1983/84 that's when mass adoption began to happen rapidly.
Also "home video sales" wasn't really a thing then either. Yeah you could rent a movie but the VHS/Beta tapes to "buy" a movie cost like $100+ (80s money). The idea of selling the movie directly to the consumer actually didn't become a common thing until the late 80s. Like you couldn't just walk into a K-Mart and buy Star Wars on VHS, the way you can buy movies today, you could rent the movie and that was it.
I know this, I grew up in the 80s and on top of that my family owned a video rental store, so I'd spend like all weekend there. I remember it all, VHS, Beta, getting posters for things like Rocky III, Robocop, The Terminator, etc. We rented not only movies but the VCRs themselves (VHS or Beta).







