Answer:
You can tumble in it, roll in it, burn it, animal eat it. Used to cover floors, still used beyond stall doors. Freshens whatever it is placed on. Absorbs whatever is poured into it.
What is as big as you are and yet does not weight anything?
I weaken all men for hours each day. I show you strange visions while you are away. I take you by night, by day take you back. None suffer to have me, but do from my lack.
You get many of me, but never enough. After the last one, your life soon will snuff. You may have one of me but one day a year, When the last one is gone, your life disappears.
Do you know what you can hold without ever touching it?
You use it between your head and your toes, the more it works the thinner it grows.