I think that Michael is tracking along behind Roth, becoming a money-laundering operation for the rough gangs on one hand while loosening the direct control he has over them with the other. The Tropigala is a flashpoint where the Roth and Corleone interests have grown so that they can't help but conflict with each other, and both react by pretending it's of no concern in order to put the other to sleep. But deal or no, I think that Michael is turning into Roth - a dirty/legitimate financial group that has the allegiance of certain rough gangs because he always makes money for his friends.