Watching some of the dogs on YouTube playing with the large balls makes me laugh. It looks like a LOT of fun! It took Ronan a week not to freak out over my own exercise ball. While he's perfectly cool with it now, even when I roll it around the room, he shows zero interest in interacting with it. He's never been interested in balls, large or small. He does like those kibble cubes though.
Now, if there were a sport where dogs collected squeaky dogs and put them in a general pile, Ronan would be all over that. He likes to 'rescue' his toys if they're too close to something spooky or in a box.