Reading another thread reminded me of an incident that happened a few years ago that I thought people might like to chime in on...
Back in 2005 or so, I was twenty years old and living in Italy. I had a friend in Ravenna, so a few of us decided to visit her for the weekend. My friends were English, and of Indian descent, so one night we decided to try the local Indian restaurant. Our waiter was also of Indian descent, and he seemed to enjoy having some English Indian girls to chat with throughout the meal. He was the only employee we saw. When we finished our meal, but before he brought the bill, he came to our table with a bottle of Indian rose liqueur. He said, "If you girls can drink this entire bottle in half an hour, your meal is free. I dare you!" We thought he was joking and laughed it off. He persisted. We very clearly asked, "Are you serious?" He confirmed that he was. "Are you REALLY serious?" He confirmed that he was. So we drank it. Maybe a little sip of rose liqueur is okay, but polishing off a 750ml bottle in thirty minutes was no small feat. After the second or third shot, I never wanted to see or smell another rose again. But, we finished the bottle. We then ASKED the waiter, "Can we REALLY go now? Are you sure?" He congratulated us for finishing and told us to have a nice night. So we walked out.
You know where this is going! We were about two blocks down the street when a woman came running out of the restaurant, screaming at us. She said she was going to call the carabinieri unless we paid for our full meal AND the bottle of rose liqueur. We were pretty drunk (no fault of our own!) but I think we were pretty polite in asking her to work it out with her waiter. She literally grabbed my friend and was pulling her back towards the restaurant, so to "free" our friend we agreed to follow her. Back in the restaurant the woman presented us with a bill for our meal and the bottle of liqueur. We turned to the server and said, "What is going on here? You told us we could go." He replied, "I thought you knew I was just joking."
In the end we paid for our food but not the liqueur, much to the displeasure of the woman. No tip, obviously. ETA: I was definitely left with the impression that it was a waiter overstepping his bounds, rather than an intentional scam. But... if you'd found yourself in a similar situation, what would you have done?