Bullshit. Salt is incredibly culinarily important and only by cooking your own food can you recognize this and more importantly, control it.

The real answer is either a) grandma doesn't cook much and hasn't since at least 1985 or b) since at least 1985 "cooking" for grandma has consisted of buying mostly prefabricated food (ie: condensed soup) and heating it up.

Also, I am a chili lover and I can taste normal food just fine.

If you think you "just don't need" salt then you likely don't do a lot of cooking. Salt is what makes food taste like shit because it isn't there. It's incredibly important, even if it is often overused. If you get premade food or are a fan of "mostly homemade," then you are likely eating way more salt than you think.

Nobody who cooks on even a semi-regular basis can go through one canister of salt in thirty fucking years.