Because, truth be told, there's no such thing as Nothing. We always do Something, even if it's watching little furry thieves snatch their overdose of sugar for the year (I wonder if the SPCA could get you for that? Luring with marshmallows. I can just see Chippy, once he's hooked, flogging his wares in the nearest dark forest alley: "Hey, you, want some snow? Three acorns, jus' for you!").
Doing Something. The question is just what that Something is. In our product-oriented society, sitting and listening to the forest is considered Nothing. And because it's Nothing, we feel guilty doing it, unless we're on a camping trip.
And that, really, is silly. The Nothing of this kind, it is Something. It feeds your soul. There are so many starving souls around, dying from lack of Nothing. Because you can't measure, weigh or count it, we don't realize we're missing it. Until we stop, and inhale the cinnamon scent of the forest floor, and feel it filling up the hollow in our soul.
Incidentally, if, on your next camping trip, you see a crazed chipmunk racing around the campsite desperately searching for something, with little flecks of white in the corners of his mouth, don't give in to him. He's already had more marshmallow this year than is good for him.