People underestimate the cost of shipping produce. If you look at banana boxes, most of them come from Ecuador (in my area).

There's a river of bananas coming from Ecuador to the US, and that river gets broken up into various tributaries which get smaller and smaller until the dribble of bananas ends up at your local store.

And then they sell for .68/lb.

Anything that makes those things last longer is something everyone wants.

In fact, in the case of bananas that variety (Cavendish) is chosen because it lasts longer. There are plenty of produce that aren't shippable because they spoil - like Hood Strawberries, which only last for a few days and are only available locally.

That's two examples, but really - the idea that producers change the expiration date is patently ridiculous, at least in the US.

Frozen food and canned goods probably never expire.

But things do break down. As a sort of ridiculous example, soda doesn't last forever for sure. And if it's in the sun or not refrigerated it gets weird.