I grew up in the 70/80s, when there was not a lot of food, and with parents who had not a lot of food growing up. Bad weather, and electricity cuts frequently, meant we mightn't get to shops for a few days, and the local shops were very expensive. So we did a "big shop" weekly, and also parents did various bulk buying things in specific places when possible (wholesaler, summer gluts from farms direct, etc).
In our house, we have plenty of money but are time poor instead. And have a DD with food issues (SNs and goes through phases of not eating various things that were loved, and having been very underweight for years, we need to make sure she does eat enough). So need a variety of nutritious foods available to choose if the plans don't work out.
And plans have a habit of changing - work goes bananas, opportunities come up that we take advantage of, there is a lot of travel and training and different things that we need to work around so need a variety of very quick to prepare meals and some that take longer for more relaxed evenings.
So I have a freezer with plenty of both raw ingredients and batch cooked meals, and also leftovers to use another day.
I have a reasonably well stocked fridge, with things like cured meats, cheese, chorizo and bacon bits, as well as short life items for the particular week - the longer life items can be used in lots of different ways.
And my store cupboard is well stocked generally - plenty of rice and pasta, tins of various types, a few different types of jars of sauce, lots of herbs and spices and basics, etc. I always have a couple of packs of wraps, and 1 pack of long life gnocchi.
My veg cupboard always has at least 2/3 onions and some garlic, and enough potatoes for 1 meal (I buy a sack once I am down to about 1-2 meals).
So I am able to make meals, probably for about 2-3 weeks at least, from what is in the house. We'd get bored, and we'd run out of milk in a couple of days, (I don't have any frozen or dried), but otherwise we'd manage fine.
Our street is well known locally for being sociable - we can decide at 4pm on Saturday to all have dinner together in 1 house so we all bring a dish. The snowy winters in 2009/10 in particular saw the beginning of a tradition of "snow BBQs" on the green outside - gas bbs going with anything from fridges/freezers (sausages, chicken, burgers etc), hot wine for adults and hot squash for DCs, and great sociability while DCs all had great fun in the snow. And yet, the local shops were always stripped bare in those events, so we needed to rely on ourselves - and we did!! There have also been a number of bad storms with high winds and flooding locally where we haven't wanted to go out unless necessary - so we rely on what we have.
As long as you stock up on things you will actually eat, and make sure to rotate your supplies so that older items get used up before going off, then having some supplies makes sense.
And I really don't have time to go to the shops every day to get whats needed - I'd love to be that kind of person, but I don't think it will ever be that relaxed in our household (or at least, not until I retire which is over 20 years away yet).