Conor points out that restaurateurs in Rome go out of their way to overcharge tourists:
Any tourist here knows the sensation: that gnawing feeling that Italians do not pay $3 for a tiny cappuccino or $4 for an unordered basket of bread.
To no one’s surprise the suspicion often reflects reality, as restaurateurs will admit in candid moments. It might be an extra 30 cents for an espresso, or a $5 tithe tacked onto a bottle of wine. It may even mean the substitution of lower grade ingredients. But the practice of charging tourists more does exist and is committed daily, even hourly. If executed properly, the turista will be none the wiser.
This is a big part of why Rome ranks dead last on my list of favorite places to visit that I have, in fact, visited. If you go to eat anywhere within a reasonable walk of the sites – and I pretty much mean anywhere – you’re going to wind up paying exorbitant sums for pretty much gawdawful food. Some of the pizza you get is so bad as to make even a native New Jerseyan (who has grown up with plenty of great pizza) long for Domino’s.
That said – if you’re willing to stay or go a bit further afield, I don’t think the above concerns hold nearly as true. The restaurant we went to in the Trastevere section, for instance, was one of the all-around best meals we’ve ever had, despite taking us about an hour and a half to reach on foot and find, even from a hotel that was already off the beaten path a bit (we were staying on the Aventine). It was also about a half to a quarter of the final bill of what we paid even at a mediocre pizzeria across the river.
Also – though it’s a lot closer to the center of tourism, Giggetto next to the Old Jewish Synagogue is not only very reasonably priced, it’s also absolutely fantastic food.