Aldi has rapidly expanded across the U.S. as it seeks to grow market share. By the end of 2018, Aldi plans to have nearly 2,000 U.S. locations, up from more than 1,600 currently.

In the St. Louis area, the grocer has nearly doubled its market share over the last two years, to about 5 percent. Schnucks is still the market leader, holding nearly 30 percent, a figure that will rise this fall as it acquires and rebrands 19 Shop ’n Save stores into Schnucks stores.

Delivery or pickup of groceries ordered online has become standard practice for chains with any scale to capture or retain market share.

Aside from Schnucks and Whole Foods, other grocers offering the service through Instacart include Fresh Thyme, Sam’s Club and Straub’s. Dierbergs offers delivery through Shipt, a subsidiary of Target.

Amazon, which acquired Whole Foods last year for $13.7 billion, allows its Prime members to receive a 10 percent discount at Missouri Whole Foods stores. Amazon is in the process of scaling its ability to offer Prime members free two-hour delivery from Whole Foods stores, although the Amazon Now service is not yet available in St. Louis.

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