it's probably also worth to mention that the lcn was founded by italian immigrants, who carried on a tradition from a country where racketeering was and to some extend still is just the way society worked - and that their succes was heavily boosted by the money and power they gained during prohibition.

Latin and black gangs started out of poverty stricken neighborhoods heavily infested with drugs and these people were generally not accepted in circles where real political and economic power could be earned. How do you think society would have reacted if a black guy tried to sell everyone on a bunch of casinos i a desert in the 40's? And by the time black and latin people reached a point where they were taken more seriously by society, the rules had started to change and it wasnt that easy to bribe your way in to the mainstream society unless you like the lcn had a solid base of power in the first place.