All restaurants in Italy have a cover charge. Two adults, two children equal four people. Three euros per person for the cover charge is normal.
Honestly I was an invite to dine at this restaurant. I will try to figure this issue and get a proper answer
3 Euro per person is really high. It is customary to get charged a cover charge (they call it something different) if the restaurant is near or overlooking a historical site or in a prime people watching area. I think the most we were charged was 2 Euro in Vernazza (Cinque Terre) the restaurant was right at the water and we had a great view, so we didn't mind all that much. The bogus charge to watch out for is the automatic charge for bread for the table per person which can range from 1.5 to 3 Euro. They will charge you the bread charge whether you plan to eat the bread or not... :(
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