Because all these payouts are based on TV channels that get bundled in with cable packages. People pay for them whether they watch or not. But now people are cutting the cord. Pretty much only older people have cable. A time is coming when they only make money off the people who actually watch their programming, and that's a much lower number.
Also, as stated above, they aren't really working to grow the game in any kind of smart or reasonable way, they are just grabbing for as much cable money as they can get while it still exists.