My Walmart, in a small town in a rural county is lucky to have six boxes total of all calibers. They don't carry guns and keep very little ammo in stock. About the only thing you can count on them maybe having is a couple of boxes of 22RF, sometimes a box of 9mm and maybe 40S&W. What is amazing is that dove, duck and goose hunting is big here and the store seldom stocks more than a box or two of shotgun shells
Hardly anyone bothers buying any ammo from them because they usually don't have any to sell. I guess the manager likes it that way.
Of course the towns one tiny gunshop doesn't have much in the way of ammo either. I think he keeps the place open as a tax write off, because he seldom has more that eight or ten guns of all kinds in the whole store, and doesn't want to be bothered special ordering anything, or acting as the FFL for something bought off gun broker. If you want anything related to guns you have to drive about 50 miles to Corpus.