FedEx drivers routinely lie about folks not being home to accept delivery, but in reality they never even go up to the door to ring the doorbell or knock on the bell. Having evidence that the driver never showed up can help dealing with FedEx to get a package that they repeatedly fail to deliver.
That's about it though, I don't actually have a doorbell camera at the moment (I did, but it died, and I haven't bothered to replace it), and I really resent the mass adoption of surveillance cameras pointed out at public roads and sidewalks, especially Ring cameras which have been repeatedly shown to be readily available to law enforcement.
Audio is well established. Video is not, therefore drawing a line before it's actually happening makes sense.
Also it's practically the last possible piece of privacy for pilots.
Also it's not been demonstrated that the significant investment in cameras, video processing, video storage, and making said video processing and storage fast enough and physically robust enough to survive crashing, is actually worthwhile.