DL can not sell the Borders movies because Lara Croft character is a property of Square Enix. And maybe most of BGMs used in the movie as well, though I am not sure as I do not play recent Tomb Raider video games. If he sells the videos, Square Enix will sue him. As the movies are free and the animater claims the project to be non-profit, the company shows generosity in overlooking the copyright infringement. The supporters are literally "suporting" the project, not buying the movies at least in official stance.