Graham: Interesting! Just to clarify, is part of your question that the *purpose* of the cash transfer (or aid in general) on the part of the donor needs to be hammered down -- i.e. is it just to improve welfare now or is there some element of righting past wrongs? I take this to be the point about (donor) obligations and the distribution of responsibility (for righting present wrongs, given historical causes/responsibilities of those wrongs.) Is this what you mean?
The second case, about the recipient's moral obligations, seems like the much tougher question.