Google have added a new optional "online only" attribute to Feed Specification in Product Search, to indicate items that’re only available for purchase online, and not available for purchase in-store or for in-store pickup. For more details on formatting the "online only" attribute, please see the Feed Specification. If you’ve local store locations and’re not yet submitting those to Google Product Search, please follow the directions here. Also, to make the visual detail as clear as possible, Google ask that when submitting a product feed, you include links to the largest highest-quality images.