I bet this type of behind the scenes selling is everywhere. In WA state there is no box limit..some guy in front of me the other day bought out all 27 boxes of .40 cal...he out loud said to his buddy (not the guy working...just some dude with him) that he might hope to resell it for about $6 more than what he was paying.
However some honest workers are still around. The older gent behind the counter was very forth coming on stuff selling super quick and the .40 stuff lasted 2 days before that happened...but the .38 stuff I wanted is never on hand...he said they only get like 2 to 3 boxes every 2 weeks and it's gone within 2 hours of hitting shelf. Didn't seem like the type to keep some for "friends".
Some walmarts sill "hold" for 24 hours....I know what that did..I doubt that's against policy. Most stores will set something aside for you if you ask nicely and say your on your way...if you don't show..it goes back on the shelf.
Another Wally World said to call each night around 7pm and ask..by then he said we normally know what's on the truck coming in the morning...
Back in the mid-90's I worked at a Kmart. Back then we sold Ammo like Walmart. I was in Sporting Goods and sold many a shotgun and rifle (we didn't sell handguns though)...back then we had plenty of ammo on the shelves for all calibers ! those were the days !! now Kmart doesn't sell the stuff (as of mid 2001 I think).