You're right, the Italian govt and anti-mafia are quick to throw out these inflated numbers about assets seized, money seized, and the huge arrests they make. It's always the most ever this, and the biggest arrest that. It gets put out in the media and that's the end of it. What they never follow up on is that most of that money/property either gets back in the hands of the family anyway, or that when mafia members are arrested in these huge sweeps, many times they are released sometime after. Could be days,weeks, or months, but when they're released so are their assets and money.
The govt doesn't follow up with the story though, it would make bad news.

They think nothing of coming to you, arresting you, taking your things and holding until you can prove your innocence, especially if you're suspected of mafia crimes.

Several years ago, someone I know in Sicily was arrested and kept in jail for 1 1/2 years until he finally proved they didn't have anything on him. They threw 8,000 EU at him for compensation for time lost and that was that.