I loan because this provides a perfect opportunity for performing acts that increase the social welfare, while remaining economically viable.
I had a professor in college remake the old adage: "Give a man a fish, and feed him for a day. Teach a man to fish, and feed him for a lifetime. Teach a man to start a fishery, and feed a whole village."
I work for a company that does large social science research. My role is to help manage the data.