This makes some assumptions.
Off the top of my head:
1) The shopkeeper is always available to grab your purchases without a wait. 2) You already know exactly which products you want, and/or there aren't different versions of products to select between. 3) The shopkeeper is trustworthy enough to get you the actual products you want. 4) You aren't a person that the shopkeeper is going to discriminate against.
There are lots of good reasons to want to pick out your own groceries.
Give me whole milk is easier and simpler than “give me this particular brand of whole milk”.
When you have needs—or even just desires—that aren't The One Available Product, suddenly you're SOL. Sometimes with grievous health consequences.
• You're able to speak loud and clear.
• You can speak the same language as the shopkeeper.
There's definitely advantages to someone picking out your groceries for you, but also some drawbacks.
even this depends on the type of shopper you are. if I'm buying a bunch of pasta, curbside pickup is great, and delivery is even better. but if I'm buying an ny strip, I want to see all the choices and pick the one that looks best. similar for fruits and vegetables, I don't trust the professional shopper to evaluate ripeness on my behalf. some things you just have to do yourself.
I think a better comparison would be people complaining about frictionless checkout (where you just walk out like Amazon grocery stores) in the same way as shopping carts, which is actually a whole new and better experience but can feel so weird that people feel uncomfortable about it.
(disclaimer: I’ve never actually tried an Amazon Go store but I do avoid self-checkout whenever I have fruits/veggies to check out)