On one hand Americans idolatry Gangs and Mafias, on the other hand Americans condemn them. Why ?

Not only are you watching too many TV shows about law enforcement, you're starting to take them seriously. TV shows are there to make money from the public. They will show whatever it is the public wants to see. Real crime is always present in our society, always has been and always will be. There is no such thing as a utopia society. In this life, there are the haves and the have-nots. The haves will do whatever it takes (both legal and illegal) to keep what they have and the have-nots will do whatever it takes (both legal and illegal)to get what they want and don't have.