It's not about scale, it's about oversight. A warrant puts a lock on the data until the request is approved. Leaving it wide open is the reason we have constant news stories about police being arrested for stalking people. Nobody wants to limit the police's ability to investigate crimes, but we do want them to use their power to investigate crimes, not to stalk their baby mama, crush, rival, etc. I fully understand and accept your point that there is no real difference between a cop watching and the cop setting (or hiring) a camera to watch, and I even believe that the more data available the more humanity benefits, and that a total absence of privacy as we know it is inevitable, I think we are not there yet culturally, so strictly requiring warrants for police to access these systems is desirable.
> Nobody wants to limit the police's ability to investigate crimes.
This is not true of privacy advocates, they do want to limit the ability to fish for circumstantial evidence that targets innocent people and causes suspicion.
I mean it's just not true at all. We don't want police to torture people for information. We don't want police to detain people for questioning, even briefly, without reasonable suspicion. We don't want police to search people or their property without a warrant. And so on.
This is non-sequitur. "Investigating crimes" entails knowledge that a crime has actually occurred, and deliberately seeking information specifically related to that crime; "fishing for circumstantial evidence" does not.
Being located in an area of a crime is circumstantial evidence. Any info on what drivers license plates drove by a camera is absolutely circumstantial evidence to a crime in the area that is known to have occurred, almost definitionally.
