Another 'non-stasher' here. I buy for projects only with a bit extra for those cutting/sewing mistakes that are bound to happen. Those leftovers are the only stash I have. I'm also not into scrappy. But there are times when I want to try a new technique or check a new block measurement, so having a variety will help with those situations. And then there is the repair factor. Had made a quilt for my niece and their dog ate a hole through the quilt. Good thing I still had those left overs and was able to fix that problem.
Do what works for you. I also simply don't have room to store a bunch of fabric.