[JDulin]

It's not for "no reason" - Public education's primary purpose in the United States, other than indoctrination, is daycare for the workforce.

So school must start early enough parents can get children to school before heading to their jobs.

[Broken_Hippo]

Before school programs exist. Daycare exists. School does not need to start early enough for parents to get children off to school first. Folks working retail, in factories, and in health care deal with this all the time.