In theory, if Walmart doesn’t have a sale item in stock when you’re at the store, they offer rain checks. Here in the real world, no one at David’s local store seems to know what a rain check is, let alone how to issue one. A rain check is a document that allows you to get the sale price on an out-of-stock item, even if the sale is over when the item comes back in stock. Apparently, it’s a relic of the era when customers couldn’t just whip out a smartphone and order the same item elsewhere at a cheaper price. That’s precisely what David did, anyway.