In short, the camera talks to the cloud for processing of events. In addition, when you log on to the app, there are also cloud communications going on. So basically, the cloud is needed for authentication and event processing regardless if you subscribe to Cam Plus or not.
With that said, my cameras are still functioning and occasionally I do get a notification. I also have SD Cards in the camera so that they will still record while the network is not accessible.
@WyzeMatt @WyzeJasonJ would you all like to add anything or clarify what I am saying?