Italian and other EU governments provide generous pensions for citizens who have spent the requisite number of years in the workforce.
If you are an American, Italian citizenship will let you invest in offshore mutual funds and securities without restriction or hindrance.
Very few foreign companies are registered to sell their securities in the United States.
According to the principle of jure sanguinis, you have actually been an Italian citizen since birth (if you qualify).
Obtaining dual citizenship through ancestry is much different than obtaining it through naturalization, which in many cases can result in the loss of your native citizenship.
Foreign brokers will not sell unregistered securities for fear of running afoul of the SEC.