Nice to see you posting, Macybaby.
I rarely, if ever, see fabric in a thrift store. (I'm not a regular thrift store shopper.) I know our local Goodwill just bales fabric with the old unsellable clothes. The closest thrift store to me that is actually a non-profit has a huge dumpster by the drop-off door and more than half of the donated stuff goes into it. The guys at the back are usually guys, so they generally don't quilt. They don't see the value there.
On the other hand, not many people quilt anymore. So the market for left over fabric is small.
A very good friend passed, and her daughter gave me all of her unfinished quilts and left over fabric. Unfortunately, she and I did not have the same taste in colors (she tended to use olive greens, peaches, and rusts, I like primary colors). so I packed up 8 "bankers boxes" of fabric, UFO's and my abandoned plans. Project Linus didn't want them ("our scrap bins are full"), my quilt guild didn't respond to my offer and most of it is still in my garage. Although I've gone through it for specific requests, my little flat dolly has become an adjunct to the guild's storeroom.
I know there are people out there who love to quilt and would like to have some of this stuff. However, I don't know how to reach them.
bkay