One side gives money, and a fraction of that money goes to the intended cause, is referred to as "fundraising". One of the more dubious aspects of donating to a charity is that some of their resources are spent persuading other people to donate to them, in what looks like a strongly zero sum game for the sector as a whole. I think there's a credible chance the system outlined here would end up at a higher effective efficiency than the current state of the art of charity fundraising.