Many restrooms in train stations in Italy are pay toilets—you pay 1 euro or so for access. (One in Mexico I went to did it one better: access was free but you paid a few pesos for a handful of toilet paper!)
The station in Ravenna was no different. However, it had been built with no way to restrict access to the restrooms, but ingenuity provided a way: they roped the doors off and stationed a woman behind a folding table with a small cash register that printed out a receipt after you handed her 1 euro.
On the way out of Ravenna I had occasion to visit it again. The table and the woman were still there, but they had taken her cash register away from her, and she instead had a printed book of receipts that she was filling out by hand.
And as far as proof goes, here’s a photo of my handwritten receipt for 1 euro for entry to a train station restroom.