The more money people have, the less they tend to do for the poor.
According to your logic, the people who do the most for the poor are the poor, which is a paradox since they have little to no resources to begin with. And I'm not sure how we expect the most wealthy to give a greater percentage of their income when we're already taking a greater percentage of it through progressive taxation. But let's go to the numbers. According to the IRS's 2011 numbers, charitable giving is on a bell curve. Apparently, the most charitable are on the income extremes.
It's a shame the middle class won't band together and come after the rich, but those poor idiot fucks won't realize that they have a better chance to win the lottery than to actually work their way into the upper echelons of society
I know you mentioned the lottery in jest, but the poor actually are the ones spending a large percentage of their meager resources on state lottery tickets. Maybe government should get out of the business of suckering poor people into gambling.