A difference in degree is a difference in kind. Computer scientists struggle with a lot of legal concepts because they love to reduce situations in attempt to distill some particular facet and argue from analogy. A lot of poor legal analysis regarding things like fraud go similarly: “well in principle isn’t this the same as if I just . . .”

If there were literally hundreds of thousands of government agents on every corner writing down every person/car that walked by, it is quite probable this would be illegal even though you have no expectation of privacy in public. See Carpenter V United States and some of the concurring opinions in United States v. Jones.