I think you had the same misunderstanding as this person: http://lesswrong.com/lw/1qf/the_craigslist_revolution_a_realworld_application/1lth In short the idea is not to give free ads for charities, but to put up normal commercial advertisements and give the proceeds to charity.
I think you had the same misunderstanding as this person: http://lesswrong.com/lw/1qf/the_craigslist_revolution_a_realworld_application/1lth In short the idea is not to give free ads for charities, but to put up normal commercial advertisements and give the proceeds to charity.