I am thinking D'Arco took advantage of Casso's and Amuso's absence and kept more than he was supposed to keep rather than kicking up everything. Casso and Amuso were far from stupid and i really believe that was D'Arco's demise.
D'Arco may have even cut a few deals with other guys telling them to say they only kicked up X amount ( less) than they really did. However, those guys gained as well by being able to keep more.
When you normally get 25k a month from a guy and now its only 10, antenna's go up.
D'Arco probably justified it by the fact that he was on the street taking the risk and he was running things, plus, lets face it, he saw an opportunity and thought he could get away with it.
This is just my own opinion but a few guys here know more than me.