I'm sure everyone of us have encountered it at some point in time. I would suggest you let it go. No matter how much we say it's about the kids some people will never understand what that truely means.
Many years ago I had to tell my best friend that his boys were not meant to wrestle. I didn't arrive at that idea based on their performance on the mat but rather dad's fits after losses. I believe wrestling IS for every kid. On the other hand, wrestling is NOT for every parent or coach!