99% of paid apps developers can't make end meet anyway. Another false dichotomy. Creating an app and sticking a price on it isn't a business model any more than creating an app and asking for donations. Both are almost certain failure. But people constantly hear about this guy or that company that made some huge success and became rich; nobody talks about the millions who failed and whose apps were simply forgotten.

Oh, and BTW, the Red Cross, Doctors without Borders, Greenpeace and many other NGOs live, AFAIK, mostly on donations. So that definitely can pay the bills, but the same reasoning applies: it's only true for a small minority, and you can't count on it.