buying Whole Foods and slashing prices on organic produce and pasta sauce, among other items, is reportedly bringing increased foot traffic to the grocery chain.

Across the U.S., Whole Foods stores saw a spike of more than 25 percent in foot traffic on Aug. 28 and 29, the first Monday and Tuesday that the merger was complete and as discounts were starting to roll out, location intelligence company Foursquare told CNBC.

Bloomberg first reported the statistics on Monday.

The volume of shoppers in stores was compared to the prior Monday and Tuesday, Aug. 21 and 22, Foursquare said, when Amazon had yet to The data were pulled from shoppers' mobile phones.

at Whole Foods stores include avocados, bananas and various meats. A store check by CNBC on Aug. 28 found that some items had been discounted by more than 40 percent. And Amazon has promised "more to come."

According to Foursquare, New York Whole Foods locations saw a lower surge in foot traffic — only 15 percent — on the first two days post-acquisition. And Chicago supermarkets saw the highest growth in shoppers — 35 percent.

To be sure, time will tell if the numbers hold, as this is still early days of the Amazon-Whole Foods combination.

Amazon is readily looking for other ways to boost sales, such as by putting Whole Foods' private-label line, 365 Everyday Value, on Amazon.com.

According to One Click Retail, an e-commerce firm that has been tracking Amazon sales, the internet giant had more than 2,000 Whole Foods items on its website in the first week that it bought the grocery chain.

Through Amazon's Fresh, Prime Now and Prime Pantry platforms, the company saw $500,000 in sales on Whole Foods items in "week one," One Click Retail found. Top sellers were coconut water, deli turkey breast and frozen fruits and vegetables, the firm added, based on its analysis.

A representative from Amazon didn't immediately respond to CNBC's request for confirmation of these statistics.

As Amazon looks to lower the average shopper's ticket at Whole Foods, a war on prices is heating up among other players in the grocery industry.

A recent price survey at grocery stores by Gordon Haskett analyst Chuck Gromm found that Wal-Mart is losing its competitive edge on discounting from players such as Target and AmazonFresh. Target just last week unveiled its plans to cut prices further.

Meantime, Kroger flaunted the success and opportunity in growing its private-label line on a recent call with analysts and investors, while German grocery players Lidl and Aldi remain in expansion mode. Everyone wants a piece of the pie.