Many people from older generations have said millennials in the workplace can be… let’s just say they don’t always see eye to eye. That disconnect can be exacerbated when long-time, knowledgeable executives have to answer to younger superiors. That seems to be the case at Whole Foods — and the older generation is having none of it.

The Wall Street Journal reported that since Amazon has taken over, more than a dozen executives and senior managers, including some in the produce division, have decided to move on, despite being asked to remain.

While the age gap certainly is a factor, the issue may in fact run deeper. According to the Journal, “Whole Foods employees said Amazon hasn’t explained the specifics of its plans to integrate the grocer into its business.”

While top end executives from Whole Foods and Amazon continue to heap praise upon each other, and that the two companies are working in concert, the Journal reported, “the exodus has raised concerns among employees and suppliers that the distinctive approach that made Whole Foods a natural and organic powerhouse won’t endure under Amazon’s ownership.”

Of course it is still too early to tell, and past history suggests that a bet against Amazon is a good way to lose your money. The Journal said some Whole Foods executives are preaching patience and that Amazon executives are “respectful and eager to learn from the grocer’s decades of experience sourcing food and handling produce.”

The Journal continued: “Others have been frustrated by what they see as Amazon’s insular culture and penchant for secrecy, according to current and former employees. ‘There really hasn’t been very much communication,’” one former executive told the WSJ.

Suppliers have noticed a difference as well. Some suppliers told the Journal that, “new hires at Whole Foods have been slow to master the chain’s techniques for sourcing and marketing healthful foods.”

Bill Caskey, co-founder of the food consultancy Pentallect Inc., told the Journal, “It makes it really difficult when you lose the institutional knowledge.”