This only works if you don't live in a dense city. People in cities simply don't have space to store (many) bulk purchases, and the stores near them (i.e. that don't need a car) don't sell things in bulk (transporting bulk items by public transport is not feasible, and it's too expensive by Uber).
When I visit friends who live in dense cities they are very excited that I have a car, and often ask me to take them to make some bulk purchases.
I don't think that's accurate. The bigger issue is economic access - poor people can't afford to stock up since they are often living paycheque to paycheque. Even middle class folks living in dense urban centres have access to car shares and delivery services. Yes there is a cost, but it's usually quite cheap.
As for storage, except for the smallest apartments, most storage spaces can be optimized quite a bit for very little cost just by purchasing containers that fit spaces properly, have good seals, and abandoning commercial packaging, especially for products that are packed for shelf appeal, not bulk storage.
Sure, that's a problem. But that's not the problem I was talking about.
> have access to car shares and delivery services. Yes there is a cost, but it's usually quite cheap.
It is most definitely not cheap! You can't buy much because you don't have room, and the cost savings of what you can buy are destroyed by this added expense, making it pointless.
> most storage spaces can be optimized quite a bit
Sure - up to a point. I mean you can also just fill your bedroom with stuff, and have a narrow corridor to walk in. But realistically, people in dense cities just don't have much space for bulk purchases.
I think "1 kilo of food per person per day" is a reasonable approximation (e.g. 1kg of dried beans is 3300 calories, 1kg of canned tuna is 1300 calories). 400 kilos of food should be enough to last a family of 4 for 3 months. Efficiently packed, you can fit 400kg of food in a 0.5m x 1m x 1m space (1 large kitchen cabinet).
It's a fair bit of space, but it's not a "fill your bedroom with stuff" amount of space.
The problem with efficiently packing that is you won't have access to it easily, in order to rotate stock.
If you are not careful you'll end up with spoiled food when you need it.
Plus there's a lot more to stock than just food - It's not just about disaster preparation, we're also trying to save money and packaging and resources.
I know this subthread is talking about saving money, but imo that shouldn't be the first priority. The first priority is avoiding disaster. Insurance costs money up front. The "cost" you are insuring against is being without food after a hurricane/blizzard/etc. If you can ALSO save money up front, that's great.
If you live in a dense city, you may be better served by getting a commercial "emergency food supply" product. A 2-week food supply from one of the major suppliers of such products is about $125 and fits in 2 5-gallon buckets. Alternatively, you can get similar foods that come in #10 cans, they store nicely under a bed.
I use these products for backpacking and they will obviously never match a real home-cooked meal but they are decent in a pinch.
That covers you for food (you will need water), and just expanding your paper goods slightly should be plenty. You're not trying to become a "prepper", you just want to get through a bad week.
I live in a downtown highrise, have a car. It works with a shelf for added storage which takes up 5 or 6 sq ft. Having the space for, say, a chest freezer, would up my game a lot but I can do plenty of bulk purchases with what I have.
When I visit friends who live in dense cities they are very excited that I have a car, and often ask me to take them to make some bulk purchases.