Then those same teachers will be hired by the private schools.
Why would you think that? Private schools can fire teachers far more easily than public schools can. And believe me, parents have far more input into what goes on in a classroom when they are paying tuition, which keeps the school going.
Not necessarily. Unlike public schools, private schools hire those who are qualified not just those who will be most likely to join the union or pass some non-consequential test which “qualifies” them to teach.
JoMa