Not sure how long ago it came about but Amazon has a Grocery area in beta with non-perishable items. It appears that a good chunk are organic or specialty items (almost 300 gluten-free items). I’m uncertain of how competitive their prices are. They do seem to have some bundle deals.

One of the new features: Shopping List. It allows you to keep track of things you buy routinely so you can order them all with ease.

And for the ngc4lib’ers, no you do not now need to offer groceries at your library. ;-)