I live a little over a mile from Wally, which means I have checked on ammo pretty frequently in recent weeks. As you might expect, the shelves are largely empty.
I know the two main sporting goods guys, so I quizzed one of them about the end of ammo sales story/rumor tonight when I grabbed a 15-round box of 20-gauge slugs. He pointed to a flatbed cart and said "That's our ammo shipment for today." There were two cases (a total of 16 25-round boxes) of Winchester 12-gauge bird shot along with the non-gun items.
"We aren't getting any .223, 9mm or .40 caliber - the stuff everyone asks for," the man said. In addition to huge demand and limited supply, I wouldn't be surprised if WM employees were buying at least some of the ammo before it hits the shelves.