As an example of how ruthless these guys can be, look at what Gerry Catena, one of the wealthiest mobsters ever, and greatly respected, had done to a bunch of innocent civilians because a grocery store would not stock a type of beach that he wanted to be on the shelves:

http://www.cosanostranews.com/2016/08/when-mafia-took-supermarket-to-war.html

Absolutely horrible, and this guy was considered to be level headed and relatively restrained compared to guys like Anastasia, Capone, Genovese, Giancana, etc. Just about all of these guys are horrible people who will stop at nothing to get what they want.