That is a really simplistic way to think about this. Most of the crops that we grow today were perfected after millenia of selective breeding and cannot be foun

That is a really simplistic way to think about this. Most of the crops that we grow today were perfected after millenia of selective breeding and cannot be found in the wild. So the only place you can find them are in human granaries and fields grown and maintained by humans. Without humans to harvest and cultivate these crops (fertilizers, tilling, irrigation) most of the crops would likely perish. Although it sounds horrible, I can certainly imagine a scenario in which some kind of catastrophe would wipe out a large section of the human race, and perhaps most of our farmers/crop growers as well. A decade after this catastrophe if a post-apocalyptic human race gains some kind of political stability, it would be immensely useful to have this kind of vault to restart agriculture.