Agreed.
Also, I think it's a matter of time before year-long school catches on. The school year evolved with long summer "vacations" because we used to live in a primarily agrarian society where the children were expected to assist with farming and harvesting.
I don't know of too many kids nowadays who work at farming and harvesting (granted I don't live in a rural area). But the point is, I don't think this applies to the majority of American school children.
I think year-long school would be beneficial to both parents and children. I think parents may have more say and more flexibility in when they can pull their kids out of school (whether that is for vacations, other educational opportunities or family obligations). Kids would likely have better retention of what they've learned. I know I forgot an awful lot of stuff over summer vacation
But, to get back on point. Yup, I think teachers are not gonna like it, but they don't need to be sharing that with the kids.