I don't fault Walmart for a rumor that was likely started by the left to stir up conservative anger toward Walmart.
Regarding that made up ammo issue, I have continued to obtain WalMart ammo (Winchester, Remington, etc), and their prices are excellent - the best around. They get 2-3 shipments a week, and expect that to go on forever. They put in a 3 box limit because people were buying WalMart's inexpensive ammo to resell at gun shows for higher prices, but otherwise no real change in policy. There is no WalMart turn away from shooting sports.
Three weeks ago I bought a Colt M4 LE 6920 for $1,097 at Walmart. I love them.