Always wondered about this, don't know if its ever been addressed. We know Marty is very good with the details. In the dinner scene at Paulie's he pulls Henry aside to ask about Billy Batts. He says to Henry, "The guy from up the street from Christy's". Is this a reference to Christy Tick? We know Pileggi and Scorsese talks about Gribbs later in the movie (obvious reference to Mr. Gribbs Carmine Tramunti), so they knew the players in the Lucchese family in the 60s/70s. It certainly seems possible.