People remote streaming won't be charged as long as the owner of the server has an active Plex Pass subscription
For users who have an active Plex Pass subscription, remote playback will continue to be available to you without interruption from any Plex Media Server, after these changes go into effect. When running your own Plex Media Server as a subscriber, other users to whom you have granted access can also stream from the server (whether local or remote), without ANY additional charge—not even a mobile activation fee.
I betting most people who are sharing their media have Plex Pass to take advantage of hardware transcoding