It’s usually vibes based, had bagged spinach in the fridge that was like a week out of date that was still usable if you just picked some bad leaves out and washed the rest, but then there’s the bag I found a few months ago that was in there for weeks after the expiration date and was just basically sludge. I used to be a lot more of a stickler about expiration dates, especially since my first job was stocking produce shelves and they hammered it into us that anything out of date was to be immediately trashed. The soy milk cartons usually say to use within a week, but they’re fine and if I’m not sure I’ll do a sniff test and a tiny taste test to make sure. Then there are times where you’d expect something to last basically forever like rice stored in a sealed container or sesame seeds in a sealed metal canister, but oh boy several years out finding them deep in the pantry they had a strong chemical taste and were 100% inedible, even if they were safe, they tasted disgusting. But chips a couple weeks out, whatever, sometimes places will sell this stuff slightly out of date for a discounted price on stuff that’s pretty clear to be safe.

Will say that the food waste from grocers and stores will outpace the home to an ungodly degree.