If only all teachers were like you. I have read message boards where teachers did nothing but bash their students. I was really shocked last week when a teacher told me (after mentioning over and over that she was a school teacher as if it made her a child expert) she did not have any children and -- like her colleagues -- did not want any. She said a lot of people should have done something else instead of having children.
In the 12 plus years I've worked in public education in California I must admit I've heard far worse than your example given here. There are teachers who should be doing something else. I've worked with some. But these are, in general, the exception rather than the rule. Most of the teachers I work with have children, and many have children with exceptional needs (Learning Disabled). These teachers have an understanding and a compassion for parents which lead them to realize that not every thing is black and white when it comes to the backgrounds and behaviors of families. My rule of thumb is that if you have a negative comment regarding a child or their parents, keep it to yourself because I won't let it slide.