I really have no idea. If you think they belong there, you are free to write the Attorney General and ask him to place them there.
"The US government supplies it to 7 people for medical purposes. Why is it a Schedule I drug?"
Those 7 are what remains of an old government marijuana study that has been discontinued. Technically, they're supposed to be submitting reports.
So you admint that MJ has some medical use and should not be subject to the stardards set forth, yet are not bothered by the obvious oversight by the government of the two substances that they prefer. You're a good, rule of law conservative, right?