> I’ve definitely noticed chips/crackers start to taste rancid not long after the expiration date.
That's because they're not expiration dates, they're "best by" dates. They're the date at which the food starts to get less tasty in various ways, but that happens much, much sooner than when the food actually becomes unsafe to eat.
Manufacturers (generally) aren't lying about those dates. They really do line up with when the food is no longer as fresh-tasting as it can possibly be. At the same time, manufacturers don't mind even a little when people confuse them with expiration dates.
Since the amount of time before food goes bad is incredibly variable and depends a ton on how it was treated after it left the manufacturer, I'm not sure that's a thing that is even possible.
But it is a thing that isn't really necessary. With the vast majority of foodstuffs, it's really easy to tell whether or not they're safe to eat by observing, smelling, or tasting them.
That's because they're not expiration dates, they're "best by" dates. They're the date at which the food starts to get less tasty in various ways, but that happens much, much sooner than when the food actually becomes unsafe to eat.
Manufacturers (generally) aren't lying about those dates. They really do line up with when the food is no longer as fresh-tasting as it can possibly be. At the same time, manufacturers don't mind even a little when people confuse them with expiration dates.