Good question.
I know I've used questionable storing practices over the years. Once upon a time, I only had fabric for the project I was working on. Then I got a deal on yard of Belfast linen. Then I got a deal on some fiddler's cloth. Then I returned stateside and found needlework stores. And more deals. I'd buy small pieces of pretty linens for ornaments. I'd buy large pieces for what I working on and save the leftover bits. I've even had people give me fabric. Then I'd buy fabric when I didn't find anything else I needed. First, it all fit nicely in a plastic shopping bag from In Stitches in Alexandria. Then it moved into an antique trunk along with bags of fibers and my patterns. Then things moved into an antique bureau, so the fabric had its own drawer. Now my fabric is in a large Rubbermaid tote. The aida tends to stay on the bottom. The linens and evenweaves float to the top. Some of it is wrapped in acid free tissue paper (that really expensive Italian stuff.)
It's funny that I don't feel any compelling desire to organize it better. Right now I enjoy going through the entire collection to see if I can find anything I can use when I start a new project. It's almost a walk down memory lane looking at the leftover pieces of fabric that match pieces I've done. I did eventually learn to label my fabric, unless it's a really small piece. I write what it is on a piece of paper and pin it to the fabric.