I have a list of movies you can't find anywhere, not even for pay, not even on on obscure services. I check every once in a while to see if they pop up (JustWatch.us is great for this, IMDB is copying). Example: "Amateur" by Hal Hartley, though it's easy enough to buy copies on DVD.

The problem is once the rights for a title end up in a library, the accessibility considerations operate at the library level, not the title level. So if some company owns the rights to "n" titles en masse, they're negotiating for the distribution rights to that library.

You can't really pull a Taylor Swift or Def Leppard "re-record for rights" move with movies.

UPDATE: Happy to be wrong about my cited example.. Thanks @andsoitis !