In the 1960s to the early 1990s the ndrangheta and the mafia in minor manner kidnapped the rich people in North Italy and made billions lires with the ransoms.
I dont think to kidnap people in NY but organizate to kidnap the son of a wealthy bussiness man and ask for money when was more hard to find someone because no cameras on the corner,no wiretrap ecc or was more profitable to kidnap powerful bosses parents like Manny Gambino?

The kidnapping and killing of Manny Gambino was done by outsiders, including Jimmy McBrateny who was killed by Gotti for doing it, Kidnapping was never a racket the mob in America got into. Maybe one or two can be found, but it is just not a thing for them here.

The probable reason is that, in the US, kidnappings always bring in the FBI, and the Mob doesn't want to provoke the FBI if they can avoid it.
The Gallos kidnapped the Profaci Family hierarchy in the early Sixties, but they weren't exactly "civilians."

In Chicago there was the Ranieri kidnapping case, the kidnapping of Factor's son, Jake Guzik was also once kidnapped, and several other examples...altough not too many.

Same thing with Contract killings. The Mob didn't do that because it would expose them to civilians and it would attract the FBI.

Sammy Gravano's crew was approached by a lawyer who wanted them to kill his wife. Sammy didn't want nothing to do with that.

One of his soldier Huck Carbonaro wanted to tell the guy he would do it then keep the money and do nothing but Sammy refused. I don't think it's an ethical thing, it's just that you don't mix the Life with civilians and you don't kill people for money.

kidnapping is a vicious crime and even most mob guys want nothing to do with it

Sell dope is not vicious?

In those days Ndrangheta earned hundreds of billions of lires, because the weak Italian authorities always paid the ransom ! A strong state should never pay ransom.

In 1990 was made a law to freeze the assets of the families of the kidnappeds. But wasnt the State that paid the ransoms,was the kidnapped people families.

The State was involved in the negotiations, who came up with the money isn't important and some other people outside the mafia also profited. Such a business model would never happen in a developed western country. Italy in those years wasn't a stable democracy a lot of (political) violence, the kidnappings were part of it..