I refold in a different way when I put fabric back into my stash after using some or just auditioning. I think it is important to put the folds in different places, especially that fold that is in it when it is on the bolt. I think it gives the fabric a chance to relax at the folds so it isn't quite so hard to get that fold line out later.
Soooo, I have a whole stack of fat quarters that have not been refolded. Not the end of the world!