I think the Canadian faction is probably more into drugs, so they get caught/talked about more. The American side of things is probably more gambling and shylocking, therefore less attention and more unknown. Sure there's probably not some secret army of American buffalo guys killing people and selling tons of coke, but i can't see the Violi's and the Canadian faction showing so much respect for Todaro if there wasn't a sizeable and relevant American component of the family. The buffalo connections probably appealed to the Violi's still in this day and age because of the good connections to the other side of the border, so easier to transport drugs across the border. It seems like they got maybe a couple of crews in Buffalo itself, so maybe give or take 10 made guys and a bunch of associates in Buffalo, and a couple of satellite crews in upstate New York, and the powerful Canadian crew.