[cprncus]

> For a video that is available online at any time, for free, it seems that there can be no distinction between the download and the stream.

But of course there is a big distinction: Google controls the stream; it doesn't control the downloaded video. With control, it can choose to a) force you to watch an ad (as you mentioned), it can b) pull a video for any reason, including copyright infringement, content objection, failure to pay a subscriber fee, etc., c) ask you to be a subscriber, for either a cost or at least registration, etc. None of that is possible if the video goes out into the wild and can be, for example, freely traded among users through file sharing or, worse, alternate video hosting and streaming by a competitor.

The videos trove is their treasure, and they guard it.