I said it's not the norm the way it is in the US and I also said it's frowned upon and not acceptable and not "cool" the way it is here. I'm right on all counts. Does it happen? Yes. Maybe even moreso within Calabrians than Sicilians. You can find articles about anything if you look hard enough, but it's still a rarity. Your article went off on a whole other tangent, than what I was talking about, too. I was strictly talking about the mistresses.
The whole concept of a mistress is what i'm saying is rare. There is no such thing as taking your mistress out on Friday and the wife is for Saturdays, again, like in the US. That is more of an Italian-American thing.

Thanks for more or less giving me your permission to "feel free to do some more research". Very kind of you.
My research comes from life, my family, and spending nearly every summer in the most mafia entrenched provinces of Sicily.