The reasoning could be speculated upon ad nauseum, but the Mafia culture here isn't like the east coast. Outside of the Mooney/Accardo era, the Outfit has never been a flashy/enticing entity. It's ugly, cold, tight-lipped, clannish, and culturally it's a very gritty/nasty in comparison with it's east coast counterparts.
This is probably the best description of the post-Giancana era Outfit I have seen. The reasons you discussed above were a major influence on why I began to concentrate more on the Outfit than the East Coast - there really was(/is?) nothing else like it.
