There is also the lack of browsing on amazon. I am fine with that for almost all other items, but something about food makes me want to walk the aisles and find food that sounds good. I do love cooking, so I might be in the minority in that regard.
I would rather walk a third of a mile to a real grocery store. That is mainly because of the produce and meats which is the bulk of my purchases. The rest of the stuff, cleaning supplies and such, I order through prime and get them in 2 days. Otherwise I would have to pay a delivery fee or meet a minimum order amount for free delivery.