But couldn't it have been that Ruggiero would have whacked Casso first? I don't think he would have just waited to die without doing anything.

Willie Marfeo to Henry Tameleo:

1) "You people want a loaf of bread and you throw the crumbs back. Well, fuck you. I ain't closing down."

2) "Get out of here, old man. Go tell Raymond to go shit in his hat. We're not giving you anything."