
I have the answer to your question. They don’t have a billion dollars, they own a company and have assets that bring their net worth to 1 billion dollars. These assets (specifically the company or companies) give employment and livelihoods to tens of thousands of people and the company is what gives the billionaire a sense of purpose and meaning. No one is just sitting around with a billion dollars doing nothing. If your point is wealthy people should be more philanthropic then I agree.