It's not their fault the bottle you brought in was corked, so you should pay the corkage fee.

If they sold you the bottle that is a different story, and they should offer you another bottle of either the same wine or something else. Some places don't do that as they don't have the relationship with their distributors to recover the money, and some will argue it's not corked, that you just didn't like the wine so you should pay it, but those are just places you don't go back to again.

Corkage fees are just a profit center for them, I don't think it's to make up for the loss of you buying a bottle of wine (some fees are more than the profit they would get from a lower priced bottle) and it's not to just cover the cost in opening a bottle and washing two glasses. If those were real costs, at a place charging $25 for the corkage fee, diet coke would have to cost like $15 a glass to cover the same cost in washing the glass.