(1) Many of the items aren't consumable items. On my page, there is a wall clock, a power strip, and an instant pot.
(2) The ordering of the items appears to be based mostly on what I bought recently rather than what I'm likely to buy over and over again consistently. (Or likely to need right now.) It could allow me to choose, but it doesn't. It could choose for me intelligently, but it isn't doing that because #2 on the list for me is a year's supply of allergy pills that I bought 3 months ago.
(3) There isn't a streamlined purchase process. The buttons just add them to my cart. (Though this could have something to do with my not having enabled one click ordering on my account.)