Much easier for the party seeking footage to subpoena a large, third party repository than to subpoena individual citizens. The mere existence of large repositories of recorded footage invites parties to subpoena them. No need to locate individuals with useful footage and subpoena each separately. Just go to Ring. This is the same with third party email providers. They make warrants and subpoenas much more convenient. Just go to Google. These are one stop shops for getting peoples' data. Why store private data on removable media disconnected from the internet. Put it in the cloud so it's easier for law enforcement to get a copy. They can subpoena the cloud provider. It's better if people do not know when the third party is giving their data to law enforcement.