I'd have to agree with the person who said, "neither generosity nor stupidity." It's dismissive to even raise the question of "stupidity," since you obviously don't believe your friend is stupid. If you want to congratulate yourself for the things you've figured out, fine, but certainly you can find a better way to do it. The word "stupid" doesn't even apply.

Almost everyone has "issues" around certain things: food, sex, money, work, etc. And only once we stop to examine the lessons we learned while growing up will we ever grow beyond our habitual patterns of behavior. Whether his behavior is manipulative, altruistic, or simply short-sighted is not a call anyone here (yourself included) can make. The only things we can say for certain is that it looks like a bad habit, and with daily practice it could be changed.

I think the real question is this: what unexamined behaviors do we have when it comes to generosity? The question might be better phrased as, "What do we get from giving?" Once we figure that one out, then we'd be able to discern when we've gone too far.