the first principle we ought to start with is that each person has the right to their own person and property, and that it is immoral to try and take it from them for any cause.
Thought experiment: A dictator happens to own all the property on the planet. Until now, he has been giving everybody exactly enough food to survive. In a fit of rage/madness, he stops. You would support the death of all humans other than the dictator, rather than taking his property?
Group social pressure is a commonly used tool in microfinance efforts. Might be worth reading about them.