IPL is the richest league in the world and naturally it features the best players. None of the other leagues can afford to spend millions of USD on each of these players. Salaries in excess of $2 million per year are not unheard in the IPL. On the other hand, we have seen players pulling out from other leagues such as the BBL and CPL, because they feel that the salary is not up to a level where they would be compelled to play. And in the end money matters for the players. Everything else is of secondary concern.
No doubt IPL is richest, and they could be more in near future as they are doing their homework with the help of ICC, but if they do some better favour for few other small boards surely this could be good for these boards and players because recently we have few players pull out from CPL, BBL and BPL due to salary issues and if this case continue then surely we will watch few leagues will die before having any good peak for themselves so it is good time for give them support.
Because, this healthy competition is very important for them and all cricket community. Right now we have IPL, PSL and Vitality Blast these are doing much better, but now few are having issues which need to settle before we are late and these disappear from sight, and we lost some good cricket from many players.