If they were allowed to use xray scanners to scan every car on every street in a city to see who and what is inside - you okay with that escalation? Because they are doing it "near" borders (backscatter on vehicles) and who knows where they will take it next.
My problem is the infinite retention of that data and the fact that many agencies use a private third party for the system. I think eliminating the scanners is a bad thing, but I would like to see some basic rules that would have to be followed.
This car location database is just the tip of the iceberg, and it happens to be absolutely unambiguously legal for gov't and corporations to do whatever they please with this data.
I am not actually paranoid. I am quite confident that the norm is for the police to have reasonable procedures in place -- the last thing a police department wants is for a police officer or former police officer to be accused of using police resources in a creepy manner to stalk/spy on an ex-spouse or similar. They want an explicit paper trial of Officer X asked about car owned by person Y for reason Z. Even if the norm is pretty good, the public should have clear expectation that can be understood.
I wouldn't, but mostly because x-ray'ing is harmful to health.