There are a few other instances which come to mind.

The spread of cable television within the US had distinct limits through the 1980s and 1990s, with much of country (by area, though not population) excluded. Satellite TV had its heyday, and regions in which it was popular (often as the only alternative to very limited over-the-air terrestrial broadcast) were referred to as "Birdland", after the dishes pointed at orbiting "birds", or satellites.

Which is a long way of saying that looking at the proliferation of cable and penetration of satellite TV might allow for some differentiation within US populations.

Back in my uni days, an example which came up was of inverse relationship between fertility and television reception within remote mountain regions in Southeast Asia (Thailand if memory serves, which it does poorly). I'm not finding that reference though there's more recent research of a similar nature:

Diffusion Processes and Fertility Transition: Selected Perspectives, Chapter 7 "Mass Media and Fertility Change" <https://www.ncbi.nlm.nih.gov/books/NBK223858/> (2001).

The general inference being that late-night TV viewing and sex were substitute activities.