Ethical question

Question

I was in a restaurant with my husband. I had ordered a pasta dish, and while I was eating it, I discovered a long piece of hair. Of course, I stopped eating it right away and called over the waitress. She, in turn, went to the owner with the dish. He came over to us and told me that the dish would be 50% off. Here are some pieces of information to factor in - the restaurant was not very full at the time, it was also summer time when they usually get a lot more business. The waitress, in the end, gave it to us for free. We will not patronize this restaurant again. Do you feel the owner behaved properly? My personal opinion is that he should have given my meal for free, if not the entire meal, and maybe even a discount the next time we come.