An American is someone who thinks the World Series really is.

(duck and cover... ;-)

Actually a ride-on lawnmower is pretty damn practical for big lawns. Reason Americans have them and Brits don't is that most Brits don't have big enough lawns to make it worthwhile. And that most British gardens reduce lawn area by being full of flowerbeds and landscaping, which seems to be relatively unusual in the States (or at least to the extent that Brits do it).