On my mind - abuses in the educational system

I recently had a conversation with my older sister who is an elementary school teacher in Colorado. She was very distressed. This is her first year teaching at her school, and she's already contemplating switching schools. Her principal is a tyrannical, power-abusing monster (my words, not hers). The principal refuses to listen to anyone's opinions about necessary changes, even if they're little things. In addition, the principal greatly dislikes one of the other teachers. This particular teacher already has tenure, so the principal can't fire her. Instead, she fires anyone who befriends this teacher. According to my sister, this principal told one of the new teachers this year, "Be careful who you make friends with and whose side you take, it could cost you your job."
This is unbelievable to me. After talking with my sister, though, I had a similar conversation with my aunt - an ESL teacher at a college in Arkansas. Her department head takes offense at any suggestions offered (even when she asks for them). At a meeting, she asked if anyone had any suggestions for improving things. My aunt suggested they rearrange the furniture in the shared department office to improve space issues. Later, the department head approached her and severely rebuked my aunt for "undermining her authority in front of their co-workers".
Seriously, how do people like this get such high positions? These abuses of power make me nervous. I always thought teachers faced enough challenges just reaching their students inside the classroom. Now I learn that they face challenges from their colleagues outside the classroom as well.