Fink is a part of society. He isn't society. He's just one guy.

Society can make collective decisions using collective mechanisms. Mostly: voting and markets. But it can also be things like organised religions, other voluntary communities and so on.

When one guy has accumulated large sums of money by promising to invest it only on the basis of yield and then turns around and starts throwing that weight around, he's effectively overriding the collective judgement of many other people who can't cause as immediate an impact on any specific firm as he can.