Why does iTunes keep prompting for password for Auto Downloads

What is the point checking off "Always check for available downloads" and "Download pre-orders when available" if iTunes isn't going to actually automatically download anything until I go to my computer and enter the password in the pop-up? I understand having to enter a password when buying something new, but why can't it just download the already paid for pre-order TV shows without me having to intervene? All that does it save one step (clicking on "Check for available downloads") and it causes my iTunes to stop or interrupt streaming to my devices such as AppleTV when that prompt is sitting on the screen.

There is no good reason this basic stuff shouldn't be completely automatic ... I should be able to go to bed at night, and when I get up in the morning and go to my AppleTV I should immediately be able to just watch any new episodes that became available during the night without having to stream them from iCloud (which means I would have to download it twice, once while streaming and again to have it on my Mac).