The fact that money was spent on those books is not a reason to use them. Children's minds are more important than money. Any decent teacher can teach the basics without a textbook, especially now with the availability of online free sources such as Kahn Academy and Cool Math academic lessons.
I have no respect for teacher who went along with Common Core without objection.
My wife teaches trig, pre-calc, calc. For a while, she had the only calc class in the region. Now I think there are one or two more.
Common Core hurts kids. No teacher should “go along” with anything that hurts children. No one is holding a gun to their heads. They hurt children for money, generous vacations, and a pension.
As for their jobs, everyone else in America has managed to find honorable work. Teachers could too.