Many companies and artists simply allow technically infringing fan art etc. to exist without enforcement.
Edit: the documentary is "Art and Craft" [1] about Mark Landis [2]
> It appears that in donating forgeries to art museums, Landis has not actually broken any laws, even though his activities were clearly deceitful. If he had sold the work to museums or taken a tax deduction on them, he might have fallen under federal art crime statutes. But the fact that he did not gain economically from his actions (apart from a few gifts from curators), and that he addressed his donations to specialists who had the expertise to detect his forgeries but did not, protected him in the eyes of the law. No legal action has been opened against him to date (as of 2014). As one art crimes expert put it: "Basically, you have a guy going around the country on his own nickel giving free stuff to museums."
No one asked, but I'll analyze the differences between these two situations. Landis didn't impersonate any living people. It wasn't done against a backdrop of living people losing their jobs. What he made was still art, in that it was both a display of technical skill and worth discussion. Slop is neither. From now on, his forgeries will be clearly labeled as forgeries any time they're displayed. That's easy to do with a physical painting, but impossible when an image has been shared across platforms.