In the US, best by dates (and other dates) are used by manufacturers to avoid quality disputes about old food. There are regulations that they have to be truthf

In the US, best by dates (and other dates) are used by manufacturers to avoid quality disputes about old food. There are regulations that they have to be truthful, but they are not required (except on infant formula). https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/food-product-dating https://www.fsis.usda.gov/food-safety/safe-food-handling-and... So there you go. Also, if you look at context, the poster I replied to asserted that salt clumping was not a change in quality (hence the form of my reply).