> It's mostly greed that prevents it
Greed is a human axiom. Anything that depends on humans not being greedy isn't worth the paper it's printed on. That's why capitalism won, despite its many faults: it requires human greed to function.
No, I don't think so. From a historical point of view, everything is quite clear: after communists came to power, the most severe famines occurred even before this totalitarian dictatorship is build, as a consequence of these very tax policies, the purpose of which is "easily feed, clothe, house everyone".
Totalitarian dictatorship comes later, as the problem transform to "we can easily feed, clothe, house everyone, but they don't want to, so we should force them"