Walmart is not deliberately ignoring quilters' requests. They only care about the bottom line--profits. To have a full fabric department, they have to pay someone to cut the fabric and they have to mark it up enough to be profitable. When it's not making the corporation enough money, they quit carrying it. Don't take it personally because they don't need to care about you; they only need to care about money, and they're making plenty of it.
I try not to buy anything from Walmart.