Almost all canned goods will last 5yrs or longer, that's a lot of canned goods for the price of one case of MREs
This is generally right on the money, despite dates on cans.
However, I can say that canned fruits will have a funny taste after about 3 years (but still be safe).
Canned milk will be off after about 2 years, both in taste and safety. (would just make you sick to your stomach)
For dairy, powdered is the way to go. This is about the only real "survivor food" I try and stock up on (powdered milk, butter, cheese, and eggs). The rest is more geared towards:
1. Livestock sources (like keeping chickens and rabbits). With chickens, you get eggs. When they stop laying, you have chicken meat. With rabbits, these things just keep on multiplying, and their short gestation and rapid growth would keep you in meat pretty well. We may get goats too, but not until next year if then.
2. Produce sources such as fruit trees and bushes, a garden for veggies, and a fresh herb and medicinal herb garden.
3. Buckets of dry beans, dry pasta, rice, cereals, popcorn, dried corn, mashed potato flakes, flour, sugar, salt
4. Home Canned foods (produce, prepared soups, stews, sauces, meats)
5. Store bought foods, dry goods, canned goods.
MREs are for on the go, like while traveling to your base, or scouting, etc. Even then, there are cheaper options. Personally, I like the dehydrated meals made for hikers over MREs, for a bug out bag, for example. The Mountain House beef stew is pretty yummy. Tried them for lunch occasionally, but not often, as $6 a pop is pretty steep for a brought lunch.