My grandmother was great depression and instead of throwing away food, we just ate it all!

...hm, wonder where my fucked up relation with food comes from. Oh well, we'll never know!

Unopened dry food doesn't expire in most cases.* Nutrition and taste may get worse, but it's not harmful.

*(properly sealed, shelf stable, reasonable time frames)

What a waste, most canned foods are good several years after the marked "best by" date.