I understand that, completely. I used to be the same way about games; I'm just confident that Amazon can sort out any issues I'd have in that regard. But, I'm forced to do the download version anyways because neither my nor my father's computer have disk drives.
Oh well, I'll just do it and see what happens. Thanks for the reply.
EDIT: For the record, buying multiple copies of the same game from the same Amazon account totally works just fine. If you buy multiple copies, you will see them all in your Amazon Game Library or whatever it's called, and it displays a key for each one. You can then download the game from U-Play or Amazon depending on your preference and use the key to activate it, presumably as many times as you want.