Realistically this only makes sense for rural dwellers.
Suppose I stockpiled a year's food? If the shit hits the fan badly enough that I need it what are the chances the electricity and water will work? This place is completely uninhabitable without both.
Also, if the shit hits the fan and I know that you have a year's supply of food, I'm totally going to murder you and steal all your food. I mean ... nothing personal ... but that's what's going to happen.
Yup, this is the other problem with being well prepared other than in rural territory.