Yes, obviously, there's someone buying it when they release it. But even in Marvel's current anemic state I doubt sales of Snow White reaches even .1% of the revenue from The Marvels, a single movie. Their revenue on direct sales of stuff about to go public domain is a rounding error, and nowhere near enough to justify locking up the entire rest of the nation's culture just for that.

Further evidence that it must not be that big a deal is that the Mouse seems to have finally relented and doesn't seem to be lobbying for more extensions anymore.