The Mexican Cartels aren't any different than the Italian Mafias or any organized crime group in the sense of honor, code of ethics etc. in some instances better. All of the people being beheaded or castrated are rivals killing rivals they don't do that to innocent people and it's actually very taboo/frowned upon in the Mexican underworld to hurt innocents in any way. Extortions or and kidnapping for ransom are the worst you can do in Mexican underworld and could/will lead you to your death depending on the state or city you're on. A lot of the people killed in Mexico are cartel enforcers killing each other and their affiliates.