As a general rule, businesses in prime locations charge more, and establishments that are known far beyond the confines of their cities charge the most. So, in Venice, you will pay a premium for eating or drinking in or very near to St. Mark's, and a higher premium for visiting Harry's Bar or Cafe Florian. I leave that sort of place to American high rollers. But if your pocket can take it, and you are so minded, I don't object to your going there.
I still think Venice is expensive: it's essentially one big tourist trap. But by using your head and a bit of energy, you can moderate the price of your visit, mainly by being careful about where to eat, drink, and shop.
I agree that it is a great place to wander around, and think it is one of the great European destinations, even for somebody like me who prefers to travel like a cheapskate.