How Bing is indexing YouTube videos?

If you go to Bing videos on Edge browser & search for any YouTube content, you can play them without any ads. Eg: https://www.bing.com/videos/search?q=youtube+free+movies&FORM=HDRSC4

Also I don't see links to youtube domain itself for videos. It is being served from Bing.

1. Can anyone index youtube videos & openly share?

2. Video quality is not as good as YouTube but there are no ads. This may be good for consumers who want to avoid ads.

3. Isn't this a copyright issue?