Burger debacle

On Friday I ordered a burger for my son. He complained of the taste so I checked and it was disgusting. The waiter took it away and said I would not be charged. I asked for a manager who confirmed they had had other complaints but it was about the spices and not because the meat was off. I asked for half a portion of wings (he is 11 and did not want any meat but he had to eat something) and was told I could not have that as only full portions are sold. I was not charged for the burger and was eventually given a full portion of wings and a R20 discount. I won't be back. Our average bill normally exceeds R500.