Back in the Before Days, I went to a presentation by a journalist who was investigating secret bases in Africa and it was kinda wild how he was able to identify them using public satellite photos and Strava uploads.
Like, netflix has to know. In a small town in Afghanistan they keep getting 50 or so IP addresses that pop up every time an episode of the boys drops in English. There is only so secret a big mitary base can be.
Or pornhub knows based on small pockets of preferences that look exactly like military bases in random places across the world.