I highly doubt any self-made billionaire who keeps pushing for more is actually pushing for more money specifically. It seems to me that more money is a side-effect of whatever they're addicted to doing.
I'm not sure I buy it. You don't get to be a billionaire by being net harmful, you do it by selling goods and services that people want, at scale, and capturing a portion of the wealth you created.
I don't know, you'd probably have to ask a billionaire that's ruining the lives of other people to earn their second (or tenth) billion.
Not all of them actively do that, but a large number very actively pursue that sort of thing.