Everything is expensive in the Paris cafes! This is typical of so many big cities, especially those that are also tourist centres. Paris isn't as expensive as many places in Venice - there are cafes there where a coffee will cost you as much as a meal somewhere else.

What I found different in Paris was that they had a very clever way of getting you to buy extras - for example, they would say 'would you like ice in your water' or something so that you thought it was included with the meal (the same dodge happened with coffee in one place - it looks like it's included in the menu but turns out to cost about 6 euros a cup).

However, it's such a great city that I think you just accept it - and after a while you learn to refuse everything unless you have both specifically asked for it and checked the price.