I've always known that Walmart will match a competitor's advertised price and the last place I lived, the Walmart had the other store's sales flyers on display in the foyer, but I've never used it nor have I ever seen anyone else do it, so I didn't know how it worked.
This afternoon my wife and I ran some errands together, one of which was Walmart. I know that I usually use the self-checkouts because they're faster and I assume my wife does the same, but two of our purchases were going to need cashier intervention, so we got into a line.
After realizing that the group of 20-somethings were going to divide their cart into three transactions, we flipped to another line that I thought would be shorter because it had only one person. Though my wife disagreed and she was right. The woman in the other line had like twenty items, but every one of them were price match, so I got a good view of how it works.
Up under the cashier stand, there was a stack of sale papers and with each item she'd tell him the store, he'd find the appropriate flyer, check the price and enter an override code. One of the items the customer said was on sale at Kroger and though he had one Kroger full-page, the cashier didn't have an insert, so he checked with the next cashier, thumbed through her stack and when he couldn't find the Kroger there, he consulted with whomever was running the front end and got approval to take the customer's word.
I noticed as we walked out that all of the other checkstands had a stack of sale papers in the same spot, including the one for self-checkout and after the dude apologized for the previous customer taking so long, he volunteered that if you come in during the off-hours, the clerks will let you look through their sale papers to see if there's something you'd like to buy.
Personally, I'm still of the school that if store X has something on sale, I'll buy it there because they made the extra effort of setting a bargain price, but because I've never seen price match in action before, I thought that I'd write it up in case some could use the info.
I might also use it someday myself, especially on a big ticket item, when Best Buy's out of stock.