I do the same thing with my strips that are at least 2-1/2 inches wide. I also roll up leftover binding the same way; I can use them on scrap quilts.

I like roll ups - they look so neat in the plastic container. And soooo easy to just pick a roll of either light/dark to start using in a quilt. I'm more apt to use scraps when they're not all jumbled up in a drawer or box waiting to be cut.