People volunteer to make billionaires even more profit - crazy world. Who even have the time and resources to volunteer so much??? I don't get all this at all.
The mixture of motivations includes a desire to contribute something to humanity, a desire to make a mark or achieve recognition, or a desire to gain experience that might enhance your ability to get hired.
It can be a hobby like model trains and it can be a a social context like joining a club or going to church.
But it's safe to say that nobody is volunteering "to make billionaires even more profit."