How so? From an Anti-Trust perspective, the FTC recently blocked the Walgreens/Rite-Aid[1] and FanDuel/DraftKings[2] deals. I'm not sure this deal is anti-competitive and certainly doesn't come off as anti-consumer to me.
However, as it relates to the FTC, I am concerned with the increasing size of Fortune 100/500 companies [3] and their relationship to the decline in entrepreneurship in the United States [4]. The biggest companies are getting bigger and growing faster than ever and the FTC affects that by reviewing M&A activity.
I agree that Whole Foods isn't a big deal merger but the fact that Amazon has a logistics system in place that could topple the other competitors is very scary. The silver lining to this is that it'll be mostly Walmart vs Amazon now rather than Walmart trying to destroy the regional chains (and Kroger to some extent on the national side of things). Hopefully this will add some competition on the Walmart front to force them to pull back where they're really not needed (or wanted).