Since I only have a 2 bedroom townhome and not enough space ... I keep my roll of batting under my bed with garbage bags around it to keep it dust free. This meant I had to put my bed on risers. Luckily I am not too short to get into bed now. I have a blanket chest at the foot of the bed so no one knows what under the bed if I don't tell them.
Since my bed is now a bit higher I have some wheeled baskets I bought years ago [they were for storage of kids toys] also under the bed and they hold the pieces of batting that was not used.
Yes, I do sew my batting together for some quilts. Usually the charity quilts as that is what we do in that group anyway.
ali