I would have assumed that someone who would go out of their way to steal somebody else's airbags would also not bother with safety inspections or whatever that might have kept their broken car from being on the road.
ALPRs with a live querying capability to the registry of motor vehicles will now flag cars with expired safety inspections around here. It's an easy ticket for the police to grab their town some cash and several local towns are fairly aggressive about ticketing for expired inspections. (You could get away without fixing airbags on a pre-OBD2 car by taking it to an inspection shop that will look the other way, but even those have to connect to OBD2 on equipped cars.)
I suspect that most people who need airbags are still buying them; they're just buying them at the end of a chain of fencing stolen bags.
I suspect that most people who need airbags are still buying them; they're just buying them at the end of a chain of fencing stolen bags.