Whose to blame in the media game?

I saw an article in the local paper,
apparently a school teacher in paterson posted something on his facebook about teaching a bunch of "future criminals."

Yes, this is pretty offensive, and yes, it is largely true.
But what does it matter? People post dumb shit on their facbeook all the time.
The difference here is that some parents noticed it, and took offense.
Then they made a big stink about it.

Why is that bad?
Because the only negative effect that the teacher's comments could have, is his students seeing it, and feeling like they have no hope in life, and even their teachers expect nothing of them, and since they're only going to be criminals when they grow up, they might as well get a head start.
And the only reason his students will see it is because the parents made a big stink of it, and it ended up in the newspaper.