most people keep their phone on them most of the day, especially those willing to grocery shop online. i don't feel like finding a phone and pressing maybe, 3 buttons, is any slower than finding some other gadget tucked in a drawer somewhere in your house, and pressing one button. i don't see the point of the hardware here, even though finding an app on my phone is apparently 4 steps.
Moms do the lion's share of household grocery shopping, and are less likely to have functional pockets than men. This gizmo is going to be hanging on the pantry door.
Amazon is creating services and products based on observed behaviors and needs in households with multiple people. You're making claims about what other people want based on how you feel.
Creating things people want and are willing to give you money for requires paying attention to what they actually do and use -- not just what they say they do, nor how you feel they should be acting.
