To me, nothing says "preparedness" like a well stocked pantry. Whether it's a hoard of stinky roleplayers, a hoard of slinky poly-folk or a hoard of radioactive muties, you want to have plenty on hand to ensure you can pull through unscathed. Not only staples, but also all the fixings to be able to do more than -survive-. Subsistence living is a morale killer and a well made meal can make all the difference to someones spirits, I've found. This is the same if you're on a tight budget financially, or if "The Big One" has come and you have to simply make do with what you can get, and resupply is a long way off. Bulk stores,
in well sealed containers are the way to go. The fact our pantry is tall and deep means we can shelve a lot, without too much hassle.
Planning for a house-full of people showing up at any time, can take a
bit of doing. Its a good discipline to have, especially with the
forethought that those skills encourage. As previously mentioned we do
a bit of urban-homesteading (the yucky squash vine miraculously became a pumpkin vine, thankfully) and
home preserving of produce but that just acts as a supplement. For our big fresh-food buys, we hit the markets, and for the even bigger storable staples, we
hit somewhere BIG. Buying in bulk gives savings, and those savings not only give you more to buy more, but also to pad out the bulk with tasty morsels and luxury items, or "just in case" purchases that might otherwise not make it to your domestic grocery list.
I wont go into what you should or shouldn't put into your grocery basket, but keep in mind the "use-by" dates, combinations of foods that can be mixed and matched to produce variety from limited resources and reducing not only wastage, but with careful selection, not stocking up on things that no one will like or eat. We often buy whole 24can slabs of canned goods, beans, corn, lentils, tomato pulp, because they keep, are modular and can be added to most meals in some way. The kids also eat them, a real bonus, in ANY situation.
So after securing your giant load of shopping, bulk TP and nappies in hand, what do you DO with it all. How much can you haul at any one go? I have a 5door RAV4 cruiser, which happens to have roof-racks and a tow-ball, but with some good Coyote-magic fueled 3D Tetris skills pretty well honed through years of moving house and international travel we can usually fill up the cargo section without encroaching on the back seat, where we have two child seats and one long-suffering teenager. Once home, we decant into the pantry, two fridges, a chest freezer and into these recognizable and ubiquitous modular storage systems that can be yanked and stacked in the back of the RAV4 at a moments notice. Stock rotation is important, not only for freshness, but to check what is being consumed, what is being rejected, and what has been forgotten. Bulk water containers, dry-goods, flour and the like all have important parts to play, as do household items like cleaning products and first aid supplies.
It all comes down to: know what you have, know what you need, know where it is, how to store it and know how to move it if the need arises.