This is a common misconception. As someone who holds many, many jobs myself, obviously I have a lot of cash. This would appear to help me, but it actually serves to help the others players who don't have league jobs. By taking so many of these jobs, I am able to secure cash to purchase training and equipment for my player. This makes me better, which makes my team better. That inspires the other players on my team and even other teams to want money, so they can make make their player awesome like mine. Thus, the cash trickles down to other players by motivating them to want to earn more cash, which they could do by taking jobs. Granted, myself and the other elite few already hold these jobs, but if we were to vacate them for some strange reason, then we'll be able to do so knowing that we motivated other players to take that job by showing them our large amounts of cash.
* Returns to diving in my money vault *
* Returns to diving in my money vault *