Those situations happen, but I they're actually a significant minority. For most, how these things work is completely magic. It's not that they don't care, it's that they have no knowledge of how the tool works. They know that they press a button on their phone and their door unlocks, and so are satisfied that it works as intended. That there is anything more to consider isn't on their radar.
Are you saying there are end-to-end encrypted home surveillance cameras for 1/5 of the price?
Or that there are cheap cameras uploading your videos to some shady server?
Unfortunately they are buried among 50 other completely incompetent competitors which are complete insecure garbage.