Self esteem.Also probably people will also check his channel and subscribe him.
So he gets stuff to post on YouTube because noone wants to see his crap, so he thought he's instead post a very popular movie so people view it a lot.
I've gotten away with YouTube stuff before just by writing paragraphs in the description about how the music or video is property of its sole owner and that by making the film I don't own it at all.
you can steal stuff as long as you aren't making money of itright
Just claim credit for then they'll think you own the copy-right.
If they take down your video I would suggest doing a complete wipe with Ccleaner, it can land you 5 years in prison if you don't.I wonder if he will believe this.
plus like $ 150 grand