I've got a load of tinned beans and yes I would eat them cold for 2 months to stay alive and probably a lot longer.
I see maybe three points to prepping. One is to be prepared for small scale disasters that might mean you can't by food or have services for say a month.
The other is to allow maybe medium term survival. The point of this is to store enough so that everyone else out there who is unprepared dies and society reestablishes some sort of equilibrium, thus lowering competition for resources and making it easier for you to survive. In this instance you need to store quite a bit maybe 6 months worth.
The third is to allow long term survival/fully independent living forever. This obviously requires a lot of kit and know how - expensive. Storing food to last you forever is impossible.
I think 1 is pretty low involvement and can be done at very low cost, so it makes little sense not to do it. 2 is harder work, requires the storage space and logistics, but probably isn't so expensive to implement so long as you rotate food etc. 3 is very costly and requires time to be devoted to learning skills, and for many people the equipment will have no dual use so you could be spending a lot of money on something that never happens.
With a bit of thought and low cost you can buy the kind of things that will see you through but you do need to apply a few brain cells. Water purifying tablets are more useful than bottled water for example, which would just get used up in no time and take up huge amounts of storage space.
The problem is people just aren't capable of thinking of what they need to do. For example my friend has a load of tinned steak and kidney pies. Great if they can be cooked, not so great to eat cold (you could eat them but they would taste foul). I wouldn't trade them for my tins of baked beans and rice pudding because I want something that I could keep down.