Out of Pod Experience

It's more about the parents not being able to accept their kids aren't the best at everything than it is the kids themselves. And it's not really about hurting their feelings as much as hurting their delusions. Most people are not equipped to face reality in this day and age, and construct idyllic fantasy worlds. If you have a problem with someone pointing out things you prefer to avoid thinking about, you can either become comfortable with it so it doesn't bother you anymore, or do something to change it. Don't freak out at people who remind you of reality.

Grown people are even worse for it in my opinion, only they've had more time to add to the complexity of their delusions, and maybe even make them believable. Most everyone has their excuses for why they failed or someone else did better than them, and that same logic is transferred to their children as extensions of themselves, rather than simply accepting they should improve or decide it's ok to be bad.

Oh, and i guarantee everyone at those sports matches knows the score, even the kids, they're just in denial about it.