I've seen Roku add unselected channels when a device is first linked to a user account, but I've never seen one loaded after that unless the user requested it. If your remote has buttons for Netflix and Disney, then pressing those buttons will bring up the option to install those channels. You can add a PIN to require its use for installing channels, so a channel can't be installed without knowing and entering the PIN. There is no way to remove those preprogrammed buttons on the remote, so pressing one will still bring up the offer to install the channel. But if someone doesn't know the PIN it won't be installed.
Dan
Roku Community Streaming Expert
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