I just went to Walmart.com to see if they had fabric on line and this is the message I found.
Find Fabric at Your Local Wal-Mart Store
Fabric is not available online at Walmart.com, but you can find a full assortment of fabric and sewing supplies at your local Wal-Mart store.
I used to work at corporate in Bentonville, and my take on that statement is that they are looking for a way to make fabrics pay for their floor space and pre-cuts may be the answer. A lot will depend on how successful this proves to be. The criteria is how much money they generate per square foot of space and how it compares with other departments.