Something to do with Ali back in the days?? i Think?? Forgot the details but i believe thats when it started.
Probably poaching each other's fighters. If you want asses in seats, you get the big names. If the other guy has the big names, you take them.
They competed against each other for control. King won. He wanted control of the heavies. King was way to gangsta for Arum back in the day