Many of these were very young and had become millionaires over night surely that would have made them targets for extortion from career criminals.
They were targeted by other dudes from their backgrounds who knew where they lived, where the stash houses were, where the safes were ,etc
Mafia button men would have stood out too much in the environments that these crack kingpins operated in.
Also as Scorcese pointed out about the Supreme team.....there was a hit put on a uniform in broad daylight..so I don't think some of the larger crews were gonna be afraid of the mob.
