If you go to a good quilt shop and they are selling fabric at $10 a yard. Most likely they paid $5 a yard but remember with all the over head costs of a business, you actual profit might only be 1.50 to 2.50 a yard. You have to sell a lot of yards to make any money.
Do you have competition in the area you live in? You are listed as in hiding so don't know where in the country you are.
I would also check with your local quilt guilds and see where those ladies buy most of their materials. If they are a Walmart/Joanne's buyer, you'll never make it.