The whole thing of men of Honor its only a relic of the past while ignorant men mostly poor peasants really believe in the oath that made him honorable people much better than noblemen or normal thugs.
With the time the oath lost all his meaning first spoken in italian after in english with only few italian words. If you ask to modern day mobster what really the word "man of honour" means they could not answer.
The difference between italians and the others is that the italians use the words honour,wise ecc while the other only tought guy.
In italy the mafias always liked the drug because you can easly made money (in this is the reason for kill or die) the other things are only words.
The camorra use the money for say to imprisoned members "if you dont want that your family get hungry, keep you mouth shout".
But even made too many create envy, for example in Gomorrah a caracther named o principe (the prince) is able to cut the coke and made more money than the other capos that for this want him dead.