Frank Bruni, restaurant critic for the New York Times, on what restaurants should do when the wrong entree is accidentally brought to you. I don’t like Bruni’s solution:

Alert the server, right when the wrong entrée arrives. That way, even if you decide you’re going to keep the entrée — which is one option, if it’s an entrée that suits you well enough and if you’re disinclined to disrupt the meals of everyone at the table — you’ve given the server and the restaurant the chance to do what’s right under these circumstances, and remove the cost of that entrée from your bill. It wasn’t what you asked for. You shouldn’t have to pay for it.

99% of the time, a wrong entree being delivered to the customer is honest mistake, either a miscommunication between the server and the customer or the server and the kitchen. It may have been intended for another table and simply got delivered to your table by mistake. It is an annoying situation, but servers and kitchen cooks, including the chef, are human and will make mistakes. What should happen is the mistake should be corrected by the restaurant, by making the dish the customer actually ordered. If the customer is happy to keep the dish accidentally delivered, that of course is fine as well. But at no point should the the entree being offered for free. There are other ways to make up for the mistake, including a free cocktail or a free dessert, the cost of which is much easier to swallow than an expensive steak or piece of fish. And in a lot of restaurants, the server will eat the cost of the mistake. By asking for a free entree, which will most certainly come out of the server’s tips as well, you will be taking potentially 30-40% of the night’s earnings from the server. Imagine how you would feel if you lost 40% of your daily wage from an honest mistake. 

Whatever you do, don’t have the attitude of this person. I never want to dine with him. Going out to eat is supposed to be fun — we’re not talking about open-heart surgery here.