And that's at a single police department. I'm sure some are better, but plenty are also worse.

In the US, this kind of abuse is why we have a Bill of Rights with a 4A which codifies a right against suspicionless searches and seizures. Since the 1700's even! They couldn't have forseen something like Flock, or even cars. But they did see widespread abuse of searches by the Crown, and understood the dangers of unchecked search power, while still acknowleging there are legit reasons for searches.

Potential good news: The judicial system in the US is slowly moving toward a, umm, shit.... a theory to expand 4A protection. The legal idea of it is, there are individual actions which do not rise to the level of being a 4A violation. But if multiple of those actions combined together would, then they collectively become a 4A violation, despite you can argue that there is no reasonable 4A protection against any one by itself.

Progress is slow, b/c slow is how it goes. But there IS movement, in prob a positive direction. That is happening b/c of the ways technology lets gov authorities combine data from many sources and directions, into a single invasive picture. This has already impacted some court cases.