[flagged]
If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.
If the devices can stream live video, and they all can, then they can stream stored video.
As to why they would do that? Online storage costs money. Some users are not comfortable having their videos stored with Amazon. Plenty of good reasons.
This isn’t some lunatic idea, local storage is literally how ALL security cameras used to work, and there are products that do exactly this. They have good reviews too.