[greymule]

I once served on a three-umpire team whose job was to cover one field throughout a SP softball tournament. Teams from all over the northeast. It was autumn, and the fences had been taken down and replaced by a chalk line 300 feet from the plate, so we rotated from plate to bases to "fence." The fence ump's job was to sit in a lawn chair outside the center field chalk line, and on long drives get up and check out whether the fielder stepped over the line, whether the ball traveled over the line, whether the ball hit the fielder's glove and then went over the line, and so on.

So there actually are games you umpire from a lawn chair.