She has been walking for exercise, and trying to increase the cardiovascular benefit by doing such things as swinging her arms, or kicking her legs out in front of her (rather like she's marching with the Russian army - it is the Russians, isn't it, who do that?)
She lives at the end of a dead-end road, so there's never anyone around to see her doing these things. But (and here's where the strange thoughts come in) she wonders occasionally about all those satellites that are trained on every inch of the earth. Do you think there's anyone around, monitoring those things, and laughing their asses off at that crazy old woman marching along on the gravel road down there?
Does anyone else remember "Candid Camera"? It was a television program where they would set up some crazy scene and lure unsuspecting passersby into doing ridiculously funny things without realizing they were being filmed. The program was on when the Bag Lady was very young and impressionable, and it set her up for life as slightly paranoid! That, and the idea that God was always watching was enough to keep the Bag Lady on the straight and narrow forever. Itchy butt? Don't scratch because someone might have a camera hidden in that spruce tree! And even if there's no camera, God can see you. Don't pick your nose, or fix your wedgie - even when you are totally alone, because there might be a camera. And God never sleeps.
So the Bag Lady wonders, if it's cloudy, and dark, and she goes out walking, swinging her arms and kicking her legs out, the satellites can't see her, right?
And God already knows she's a lunatic!!