It's odd that teaching unions get so much hate in the USA when there are way more objectional forms of public sector unionism (I don't just mean 'hur dur police unions' either).
Sons and daughters are more important than toilets and automobiles, and harder to replace. It doesn't really matter that much if an overpaid bum and damages your car or your plumbing. Not in the grand scheme of things, but if a teacher bullies and antagonizes your child, but can't be fired, it will bother you. Deeply. You may one day understand this.