Your suggesting feels good at a personal connection scale (i.e. you fixed my bug painpoint, have some dosh), but really to get the sort of traction where the do

Your suggesting feels good at a personal connection scale (i.e. you fixed my bug painpoint, have some dosh), but really to get the sort of traction where the donations are viable you'd be working at a much larger scale right? Plus, why should the donator does each do this all headwork? Charities make it easy to donate for a reason, it increases donations... Specifically on the topic of scale, if the donations are small enough to not run into this problem, they are probably too little to impact anything, hence scale matters if the donations do.