1. They don't know the lay of the land too well and don't have connections to establish bread-and-butter street rackets.
2. Street gangs and other ethnic OC groups have beat them to the punch. Why would those group work with out-of-towners in shy-locking and traditional mob rackets when they're already making a fortune on drugs?
3. No one to recruit once they get there, gangs thrive on personal ties, people they can trust to not rat or be too greedy. Who's going to be loyal to a bunch of guys sail in to town from New York. See point 1 also. They'd have to import soldiers, weakening already weakened families.
4. They're struggling to maintain what they already have. Who's going to stretch their resources on a big gamble in an area where cosa nostra has already been wiped-out.
5. Not too many major cities have a cohesive Italian emigrant population (or Sicilian, if the family is old school) like New York does. The ones that do still have an active cosa nostra group.
1. You have to start somewhere
2. Most ethnic street gangs don't deal in gambling and juice. They deal in drugs. Besides, I'm not talking about going into Gary Indiana. I'm talking about the suburbs of major cities. Those people gamble too.
3. You send a made man and a few associates. The families have a bunch of brokesters and troublemakers who aren't earning. Send them to another city to start up gambling operations. You have to start somewhere. How did those bookies get started?
4. I don't think they're struggling to maintain a hold in NY/NJ. The gambling and juice rackets there are saturated.
5. If the mob can only operate in cohesive Italian neighborhoods, then they are doomed. The Little Italy in KC is about 4 square blocks. There is no little Italy in Detroit and barely anything left in Chicago. The fact is, everyone gambles and gamblers lose and borrow money. There was no Italian community in Las Vegas and the mob had a lock on that city.
