For most random things, getting there and back aside, find the item in a huge store is a pain in the ass. On amazon, it's literally a 10s search query.

Also, for more common items such as shampoo or litter, grocery stores have literally 30 different types of them, which can make it hard to choose. By having ratings, reviews, information and q&a right there, it makes choosing the right product much easier.

>>15 minutes of synchronous time waiting at the store versus

Uhh, what about traveling to and from the store? Or have you invented teleportation?