I don't have any statistics or research, but this comes from personal experience in my home country. A bunch of millionaires put a lot of money in universities, schools, libraries, many fund parks and recreational spots.

There was a pretty famous one who financed the computer hardware for one tech academy and had an internship program for its students at his business. Non tech millionaires would often fund things like marathons or other sports activities. One radio station that had its HQ near a national monument would spend a portion of its income on maintenance, etc., etc.