If you had photos of your vehicle, presumably you'd know where you took it.
The idea here is that you find a picture of your vehicle that the thief took, and use this to find the location of where the thief has your vehicle.
Why would a thief post a photo of a stolen vehicle? Are they trying to sell it whole? I can't imagine that is very common, since the buyer won't be able to register it, right? Aren't most stolen vehicles disassembled (chop shops, etc)?
That seems like a pretty rare situation compared to any number of alternative use cases. Most of which are decidedly less wholesome.