Back when ammo was still either scarce or expensive or both, I went into a WalMart and they actually had 2 of the 500 round spam cans of .223 in the case that were $120 apiece. I asked the girl running the sporting goods circus about them and she told me she could not sell them to anyone. I asked why and she told me that when the 2 cans came in, they didn't get the UPC labels with them. Because they didn't have the UPC number or barcode for them, she was unable to ring them up. She said they had been there for months and that people were constantly trying to buy them, but without the UPC labels, it was impossible to scan them or ring them up. She basically said that they weren't able to look them up in the system, and unless/until they got some more in with the UPC codes on them, they wouldn't be able to sell them. I asked her if I could buy them if I could find the right UPC code for them and she told me that if I had the correct UPC code, then she should be able to print new labels and then ring them up. So, I pulled out my phone, located the correct UPC code, and gave it to her. She then ran it through the register a few times (it rejected it a couple of times, because apparently, on some products, you don't enter either the first or the last number or both of the UPC code when you do it manually) and the register finally took it. She then went and printed the labels and sold me both cans.