"Over time, there could be other formats that evolve that- that might- wouldn't be branded Whole Foods Market, potentially, wouldn't be our standards", Mackey explained. "This would be the way that Amazon and Whole Foods expands into the mid-to-low income shopper households". Whole Foods has a reputation for high quality products and one of its stores is a short distance away from most people.
While the rise of e-commerce sites has already been hurting traditional retailers, Costco may have been relatively insulated from online pressures due to its subscription model, according to Trussell.
So why would anyone assume Amazon's acquisition of Whole Foods would face regulatory scrutiny? I think we're gonna get a lot of those innovations in our stores.
Stevens shared a sentiment expressed by other aficionados: excitement about the convenience of getting groceries from the store delivered to her mixed with concern about changes to a company that helped pioneer the organic-food market in the U.S.
Drew Herdener, an Amazon spokesman, said in a statement the company has "no plans to use no-checkout technology to automate the jobs of cashiers at Whole Foods and no job reductions are planned".
Any buyer of Whole Foods would likely argue that it was not in the same market, said Alden Abbott, an antitrust expert with the Heritage Foundation.
Amazon hopes that the move will help differentiate Whole Foods from other grocers. "And I said, 'I know".More news: South Africa win thriller against England, tie up T20 series
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Amazon shares opened at $1,017, a record, although they later came down to around $1,000, up 1.28 percent from the close Friday, the day the $13.7 billion Whole Foods deal was announced.
"This transaction is going to change the landscape of how you buy food", Mickey Chadha, Moody's vice president and senior credit officer who covers Whole Foods, told CNBC's "Squawk Box" on Monday morning.
The sale still needs approval from whole foods shareholders but the deal is expected to be wrapped up later this year.
Despite that possibility, Amazon shares also gained as Wall Street analysts lauded the proposed $42-per-share deal and bet that the company would prevail in any bidding battle.
While Mackey insisted Whole Foods would keep commitment it high-quality, natural and organic foods, he also said that there could be spinoff retailers and brands that wouldn't necessarily play by the same rules.
Those of us in the industry have known for a while that Whole Foods has been pressured to sell by its activist investor Jana Partners and mutual-fund manager Neuberger Berman, and rumors of potential deals with everyone from Kroger to Albertsons have been bandied about.