LOS ANGELES (Reuters) - Shoppers are making more quick trips to Whole Foods stores that have installed Amazon.com AMZN.O lockers, giving the natural and organic retailer a new way to boost sales, research from location data advertising firm inMarket showed on Monday.

FILE PHOTO: A Whole Foods Market store is seen in Santa Monica, California, U.S. March 19, 2018. REUTERS/Lucy Nicholson

Short “micro” visits, defined as three to five minutes in length, were up 11 percent at stores with lockers since Amazon closed its purchase of Whole Foods on Aug. 28, according to an inMarket report provided exclusively to Reuters News.

That compares with the 7 percent gain at stores in the same cities that do not have the banks of lockers, inMarket said.

Amazon shoppers, including those seeking to avoid “porch pirate” package thefts, can choose to have their orders sent to a locker for one-time use at no additional cost. Amazon sends the customer the locker number and a unique code to open it and collect their package.

The firm studied 98 stores in the New York, Los Angeles, Chicago, Philadelphia, Dallas-Fort Worth, San Francisco, Washington, Houston, Boston and Atlanta metro areas. Some 76 stores, or about 16 percent the chain’s 473 stores, had lockers.

People who stop at Whole Foods to retrieve a package from an Amazon locker could be tempted to buy a drink, milk or a promoted item, said experts, who added that the trips are also a way for the retailer to keep shoppers abreast of changes at the chain.

“There’s a serendipity and immediacy to the in-store experience,” said Todd Dipaola, chief executive and founder of inMarket, which analyzes anonymous location data from the mobile devices of 50 million U.S. consumers.

“As good as delivery is getting - one-day delivery, sometimes one-hour delivery - that still can’t compete with the one-second immediacy of being in store and picking up that avocado that I’m about to make guacamole out of because I thought about it in that moment,” Dipaola said.

Micro visits have accounted for about 9 percent of all visits to grocery sellers so far this year, with Whole Foods lagging at 6.5 percent, inMarket said.

Representatives from Amazon and Whole Foods did not comment.

Whole Foods can drive impulse sales by placing products adjacent to lockers and providing quick and easy payment options, such as self-checkout, said Stewart Samuel, program director for IGD Services. He added that the chain already has tested an impulse/food-to-go area within a larger store in New York.

“While this would be additional volume for Whole Foods Market, the impact on the convenience store channel overall would be negligible,” Samuel said.

Amazon has lockers in 7-Eleven Inc convenience stores in more than 300 cities, according to published reports. Representatives from 7-Eleven did not comment for this story.