In short, celebrities often make a lot of money simply because their work generates more sales, so they get a portion of those large sales. The players know how much is made from them playing in just one game, and the networks need them to play to earn that money. So they are paid a portion of what is earned.
Did Steve Jobs leave his daughter any money?
Lisa Brennan-Jobs, now a 42 year old author and a Harvard graduate, had a different experience growing up with her father than her half-siblings. After his death, Steve Jobs did make sure to leave Lisa with a multi-million dollar inheritance.