movies (well, 99% of them) require no brain-power to enjoy
I don't think so. Have you ever seen a good movie? Memento, American Beauty, Adaptation, Se7en, Do the Right Thing, and even Pulp Fiction require quite a bit of thought to fully understand. There are COUNTLESS others.
This statement doesn't even come close to disproving the original statistic (and remember, 67% of statistics are made up on the spot).
There may be COUNTLESS (read as many) movies that require some thought, but there are SO MANY MORE (read as so many more) that don't.