There is a HUGE difference between good folks like you and the majority of idiots out there posing as parents these days.
Most parents these days would rather be "friends" with their kids rather than be PARENTS.
Mr. Stephens has probably had just about enough of these "friend" parents, and just had a reactionary snap.
I don't blame him at all.
And I agree with the poster above: creepy is a good word.
So, he couldn't control his overwrought emotions and behaved like, as you say, a spoiled brat.
I would have broken the guy's arm.