I store food and other supplies at a friends home a few miles away. I store similar supplies for them.
We each check our off site supplies once a year.
This could be useful if any localised disaster destroyed supplies at one address.
Such arrangements are not totally reliable as others post, but still better IMHO than putting all ones eggs in one basket.

I keep more extensive supplies at a relatives much furthur away, good for any long term or large scale disaster but not readily accesable without transport.

I also store basic supplies at work, food for 2 weeks, water purification tablets etc.
For short term needs what matters is calories. IMHO people worry far too much about a balanced diet in the short term, it only really matters for the long term.
15 each of large chocolate bars, tins of tuna, and packs of biscuits, will sustain an active life for a couple of weeks, or a sedentary life for perhaps twice as long.
These supplies are not bulky, nor perishable, and require no preperation.