Is it normal that my mom got super shocked over an expiry date?

Well, it would be pretty surprising to learn that you had 8-year-old seaweed sheets in your cupboard.

Microorganisms like bacteria and moulds cannot grow and multiply on or in anything where there's no moisture at all. As long as the nori package hadn't been opened and so exposed to the humidity in the air - and assuming the sheets were completely dry when packed, the wrapper was properly sealed and it was kept in the famous cool, dry place - the sheets were probably safe to eat and would have probably tasted pretty much the same as when new.

Nori contains virtually no fat, so there's no chance of it going rancid. Even if the pack had been opened at some point and the nori absorbed a little moisture, the carbohydrate and protein content of nori is so low that there's really not much there for moulds and other microorganisms to chow down on.

I'm always a little sceptical about Use By dates and extremely sceptical of Best Before dates. Generally, Use By dates are reasonably accurate, but not always. A few months ago, we discovered an unopened plastic 1 litre bucket of vanilla yoghurt at the back of our fridge which had a Use By date that had passed six months before. My wife wanted to chuck it, but I decided to have a look first. When I opened it I found that it looked and smelled exactly the same as fresh yoghurt, and it tasted fine too. So over the next few days I finished the whole container and suffered no bad consequences. On the other hand, I have occasionally wondered if milk producers in the UK put something in the milk which ensures that, on the morning of the Use By date on the bottle, the milk suddenly has a faint sour taste that wasn't there the night before.

As far as Best Before dates are concerned, I'm sure those are usually just wild guesses by the food producers. We have bees and sell honey, and the food labelling laws in the UK require us to put a Best Before date on the labels. But this is actually absurd, since honey is a food that simply does not go bad as long as it's not diluted. All honey will crystallise at some point, but it's still perfectly edible and there will be no nasty microorganisms growing in it. So we just pick a date five years in advance when we order batches of labels for our honey jars.

i worked in a wayer bottlin plant years ago

all the bottlesa perfectly clean filtered fresh mountain spring water that was tested daily had a 2 year expiration date because government laws

Nasty! I have a stupid phobia of expiring foods and products. Not in the sense that the dates scare me or the food/product will magically go bad on that date, but more in the sense that it’s unnerving when people tell me a food/product is a few months past the date and expect me to eat/use it like noting is wrong with it.