Ramesh's question is deeper than might appear at first blush.
If poor people were found to be making sub-optimal choices when they buy food (which of course most would, on a pure calories-per-dollar basis), would we then put them on nutritional education programs? That would likely save them a lot more of those pennies and dollars.
Tim, I am not sure I agree with your diagnosis of the "core problem." If we found an excellent way of "delivering" financial education, are you so sure that you'd know what you'd want to teach them?