If Venice is on your itinerary please do some reading up on the rip off in the restaurants , particularly on St Marks Square.
I don't know if you see the reports on your side on the pond but our press has carried reports of horrendous tourist rip offs , like 500 euro for some fried fish-which BTW is priced per 100 grms!
Hopefully the OP uses the link I provided earlier in which I said...
Of course if you are cruising you don't have contact with hotel housekeeping staff. But an employee of a small grocery store, a museum guard, a police man, all might serve just as well. Just simply walking about Venice you will stumble on many restaurants tucked between some building and many are reasonable and quite good.