Rusty, as long as the tins aint rusty, tinned food lasts for a few years. Food is vaccuum sealed as it goes into the tin. Probably stays fresher for longer and retains more nutrients etc, than if you buy what you think is 'fresh' food from most supermarkets
Lol, I don't think they'll have too much to look back on really pesky. For years now most kids don't do f**k all.
Nesting, hedge hopping, camping, proper camping with just a tent and a couple of very basic bits of gear, are all alien things to them.