Guys just wait and see, as I said it all revolves around the concept of "permanent establishment" and it will be for Ryanair and alikes to prove that they have absolutely nothing to do with Italy.
And it will be for the judges to determine if 10 bases, around 40 aircraft and 1000s of staff are absolutely ok to work and often live in a country where they ,according to Ryanair, are not subject to any local law.
No one is guilty of an offence untill it has been proven in a court of law, at the moment Ryanair is only under investigation and this has yet to come to court.
I appreciate the concept A&C and I even support it, having said that I knew Adolf Eichmann was guilty well before the Israelis brought him to justice.