One restaurant even charged a service fee.
Service fee is another thing. Is the part elsewhere called "pane e coperto". Not all restaurants still do it, but is a old tradition in Italy. Is not related to tipping and the amount is mandatory written on the menu.
Every restaurant in Florence requested tips. None of them had options on the credit card machine to not give a tip & you were not allowed to bypass it .
Where there are a lot of foreign tourists (mostly Americans) tips are nowadays required. Is interesting the matter that you can tip by Credit Card machine, because is not a "black" tipping in cash. Is a recorded transfer of money, so they pay taxes on it.
The great difference between being an American in over-touristy places: at the end of the meal the tourist must leave a tip. When you are an Italian in places without American tourists the waiter offer you a glass of limoncello or nocino! Or in a market sellers offer you something to eat: a piece of cake, of cheese, or chocolate.
I work as a guide and I noted that in the last year if a group of tourists (with a tour leader from Tuscany or Rome) ask me about tipping the TL warns me to don't say that tipping is not required in Italy. There are even a lot of foreign Tour Operators who warn tourists that in Italy is normal (and mandatory) leave a 10% of tip!