Yes, it is brilliant - except that using one's buttocks to operate the remote is inefficient. It uses much larger muscles than oh, say, a keypad in the arm of the couch, and so it would take more energy. But then Wally has 6 months to figure that out and implement it in the next prototype.
And yes, since it's part of the comic strip, of course it's copyrighted.
What happens after/during a Superbowl party - all those beers, hot dogs, pizza, subs, hamburgers. etc. are GOING to produce the usual result of farts. I'd imagine that would be a problem for the click-detector......