... when flying over water the crazy things the guys in those motorboats do? I see 'em do dounuts and eights and all sorts 'o things an' half the time the've got water skiers on their backs.
'S fun to race 'em, even if the don't know it. 
Of course they turn circles.
Most places, attempts at boating XC end way too soon, accompanied by expensive noises.
On a more serious note, really, look again. Unless on the Great Lakes, a river or open ocean, those poor guys are stuck in a little pond. They don't enjoy the freedom that we have, whether in a 310 or an ultralight, a sailplane or a Learjet. And they spend more on their boats than I've spent for some airplanes! While we can decide to "go look over here," all they can look at is the sides of the bathtub they've towed their boat all those miles to get to. About all the thrill they can have is to hop their own wakes.
I've had boats, even live-aboards, and they have their uses, but to be stuck on the water your whole life isn't a lot better than being stuck on the ground.