I might be misremembering or misinterpreting, but wasn't Charlotte into this kind of stuff? Certainly seem to remember her talking about her "EDC" and hunting rabbits.
Generators: Most shops and small businesses in Indian towns have a diesel generator chained up on the pavement for the daily "load shedding." It makes city centres unbearably noisy and stinky (as well as cluttering the pavements even more). Larger businesses and critical places like hospitals have large generators built into a basement or a separate building, and they tend to run far quieter and cleaner. Some people have UPSes at home but most people just make do with rechargeable LED lanterns.
Very occasionally there were water shortages too. Mains water was turned on three times a week to fill a sump from which it would be pumped to a 1,000 litre roof tank (plenty for three flats, larger buildings would have larger tanks). On one or two occasions this didn't work (maybe someone forgot to pay the man in charge of the valve, maybe something was actually broken) and then you could call out a private tanker. Far more annoying was the occasion the galoots on the ground floor went away for the weekend leaving a tap on, draining the roof tank (the tailor who had a little shop in the same building conjured up a key from somewhere and sorted it). There was also an occasion when the supply was contaminated (not that it was really safe to drink unboiled but on this occasion it was probably not safe even boiled) and the Corporation actually came round telling everyone not to use it. It turned out the people opposite had a ground well with good water and didn't mind the whole street using it in these circumstances. But I think those all count as examples of neighbourhood resilience in a community that's used to these events; no guarantee at all that similar things would happen or work here, and not just because we're not used to them.
I did enthusiastically mantain the tinned food/water reserve that the government recommended after 9/11 - but I stopped when I moved house.
I don't think I've heard of this before, probably because I was in
ABROAD at the time. Hard at this distance to say whether I would have done so but I'm inclined to think I wouldn't have bothered.