Amazon has found itself in the rare position of playing catch-up with its rivals.

The e-commerce giant announced Wednesday that its Whole Foods stores will allow customers to order their groceries online and pick them up in person. Walmart, the nation’s largest grocer, already offers online grocery pickup in nearly 1,800 stores across the United States, and plans to roll out the service to as many as 2,200 stores by the end of the year.

Amazon’s new service is starting in Sacramento and Virginia Beach. Shoppers who pay the Amazon Prime subscription fee — $12.99 a month or $119 a year — can order their groceries online and pick them up 30 minutes later at a Whole Foods.

The latest move comes as Amazon and Walmart vie head-to-head for dominance of America’s shifting retail landscape. Amazon continues to rule pure online shopping, but Walmart has been making inroads by incorporating digital shopping with its vast network of super centers. Fresh food is where the competition is perhaps the most fierce because customers shop for it so frequently.

Retailers may be doubling down on their online grocery offerings, but is this what consumers want?

Apparently not. A recent research report by analysts at Morgan Stanley says retailers still haven’t quite convinced shoppers of the merits of online grocery shopping.