I love the "not all" argument (you know, the "they're not all bad" as if that equals "none are bad"), as if any large group is ever 100% unanimous.  And as if anyone ever seriously makes the argument that 100% of a group holds a particular view: for example, even when all the Japanese were interned during WWII, no-one held the view that every single one of them was a Japanese agent.  But I've heard of no other teacher group speaking out saying this union position does not represent them.  So, in fact, I can just as easily opine (as you did, you gave zero evidence) that the union does represent all teachers.