I think all the reasons you suggested are valid Missy. I think that much money did scare him and that it did make him feel good to give to others...as you said, it gave him an emotional high.
I do think it was to buy people's affection and loyalty as well too being that he was given a hard time growing up in a poor family and in high school because he chose to look so different. That in itself was a cry for attention. He was a very insecure individual all his life.