I used to pull batting apart, and yes, it is hard on the hands.
Now I sew most of it together with a zig-zag stitch and use it in utility quilts.
The pulled apart stuff makes good stuffing for pillows for humans, too. I have made a few sets of matching pillows for little kids and their dolls. I have a few soft ones in the car for cat naps, and several near the couch for longer naps.