KJ, if you believe the mob has left sin city I suspect that you are mistaken.
They've "sanitized" and used their money to buy into legit businesses and enterprises.
The mob tried to build a false front of respectability in order to get casinos built in Atlantic City, i.e. put on a "clean" face, when the true ones in control were mobsters.
Read "The Boardwalk Jungle" for info about that if interested.
They don't own publicly traded corps like MGM, but I suspect some of the smaller casino operations in town still have, ahem, "connections."
No proof, just my suspicion.
The mob may still have some influence in certain unions in sin city, for example concessions such as laundry (they used to, anyway, per my understanding).
Why would a blood sucking flea leave a dog just because he starts to scratch?
This is just my suspicion and I could be completely wrong, but there it is.