The caveat being that these things are only doing cell tower triangulation, and not even a good job of it. So all it will be able to tell you is that your car is somewhere on the east side of the city or so. Although you will be able to listen in on the conversations of the car thieves and might pick up a clue from that.
Realistically, these are 100% for stalking/espionage.
I took the exact opposite conclusion from this information. How is it useful for stalking if it doesn't give more exact location? On the other hand if I'm looking for my own car that somebody took out of the city, this at least gives me a general idea of its location.
For stalking/espionage, approximate locations (especially which can be refined over long observation periods and combined with other data) are often fine. Patterns like when does someone leave for work, what shifts do they work, where do they go on weekends, etc can be quite apparent.
If your car is stolen, what good is knowing the general location?
Hmm, I guess my eurothinking is showing. I work and live within a 5 km radius. I guess in the US you can get much more useful that's even though it's approximate.
If my car is stolen and taken away, at least I can call that city/country police instead of waiting when it gets through the bureaucracy.
It's packaging says "data cable", not a "car tracking device". Why would they use misleading packaging that the thieves would never see? Obviously it is meant to be used as a present, or for example, for an employee bringing this "cable" to work.
Realistically, these are 100% for stalking/espionage.