To me, it's like dealing with customers at the day job. You have customers who will say things when their service, food, product has something wrong/issue with it...You have to use some tact and people skills, give some reassurance and move on. I don't like "owing one" for the above mentione reason....When are you going to make it known that, "That" was the one you made up?
I agree with the answer questions not comments...."That's gotta be a foul!" is my favorite...I keep going and they'll usually answer their own question when I don't respond.
I use some wit/funny stuff if I know the coaches....