I've never understood the appeal of online groceries. I've supported three different CSAs, and eventually canceled all three.
I buy fresh produce and high quality meat. I buy enough to eat for 3 days or so, and then buy more fresh food.
If I had 5 kids at home and went through three boxes of cereal and a gallon of milk a day, and had a meal plan, then the programmatic approach to shopping would work fine.
But I like walking around and looking at the produce. Smelling what is fresh and tasty-smelling. Making up recipes in my head, depending on what "looks good."
Online food just isn't ever going to appeal to me, I think.