A more active family is going to be seen as a greater organized crime threat by law enforcement, which in turn means more indictments. There being less indictments in Chicago and Detroit doesn't mean these families just know how to stay under the radar. It means they are smaller and there is less activity by these families when compared to those in New York.
Meaning that the Feds have bigger fish to fry.
And don't forget that the anti-terrorism squad has taken a good deal of OC agents and reassigned them. So they're not likely to put much effort into prosecuting a glorified gang in the midwest.
"I got news for you. If it wasn't for the toilet, there would be no books." --- George Costanza.
