When I bought fabric on eBay, it was billed as "quilt-quality" fabric, but it was very thin and unsuitable for quilting. When I emailed the lady I bought it from, she would not respond until I gave her a lousy rating then she attacked me saying I was too picky and warned other sellers from selling to me. Well, yes, I am picky about my quilting fabric so I don't buy on eBay.
Even when they manufacturer/designer are familiar, I know that they also make the same-appearing fabric in Wal-Mart that I find in my LQS, but they are not made from the same quality greige goods. Besides, I can find fabulous deals online from mortar quilt stores...probably pay less than I would on eBay!