Having been a vendor at a quilt show, I can tell you that some shows allow only a % of your goods to be below market value in order to protect the other vendors who are selling at retail (or close to it). I think contacting quilt guilds within a reasonable distance and asking if you could have a sale would be the best way to go. You could "grease their palms" by
offering them 10% of your sales, or fabric that doesn't sell, to aid in charitable work that they might participate in. Good Luck!