But if the extra time is not instructional, I want the option of choosing how it's spent.
Fine, you want that option, so don't send your child to a school like the one my DS goes to. But what you said, in the post that (I hope accidentally) implied that I must be either offering my son a bad home environment or making a bad choice of school for him, was
As for a longer school day, the only time that is good is when there's a bad home environment.
You could work 9-5, you could work nights, you could have a nanny, you could take off from work early on a Monday to take your child to piano lessons. If they're doing the group sport at 1pm and math at 5:30 I don't have that option.
Are we talking about you or me? You don't know which of those options I have, actually. And as it happens my son has perfectly good piano lessons in school.
