Houston does it. They have bluetooth trackers on all the highways. They use it for determining congestion based on how often you can ping the same address. Keeps pinging? Gridlock. Pings once, traffic moving.

I wander if anyone has any proof it's being stored for future use or used for anything but general traffic data.

Not sure what they’re pointing to, but TPMS tracking is possible as well.

https://youtu.be/TDYoo7TGNcw

Sure, here's the one I've had experience with: https://addinsight.com.au/

They put powerful bluetooth sensors on poles or in roadside cabinets. They're pretty cheap to deploy so have become widely used.

Pretty much if you have two bluetooth devices talking to each other, you can be tracked by your bluetooth mac address. (Same as wifi networks and sniffing with wireshark etc)

Or if you have a device pinging with a non-random mac (ie your car).

If you've got an iphone and it's not actively being used, you get a random mac, no problems.

Here is a slide deck from DEFCON on it: https://media.defcon.org/DEF%20CON%2022/DEF%20CON%2022%20pre...