I just finished Sam Walton's Book "Made in America". It's about Walmart, but I heard somewhere it's required reading for all Amazon managers. Anyway, it's a fantastic book, and there's something about their Anti-Union stance in it: "I have always believed strongly that we don’t need unions at Wal-Mart. Theoretically, I understand the argument that unions try to make, that the associates need someone to represent them…
With that in mind, I'd point out that the history of unionisation in America (and everywhere) is one of extensive bloodshed as employees have died both from unsafe labour practices [1], as well as from outright murder, intimidation and other attempts at shutting down organisation of labour.
So, yeah, it's divisive. May 1st as the international day for labour demonstrations was put in place to commemorate the Chicago Haymarket Massacre [2], on the request of what is now the AFL-CIO, and to resume the fight for the 8 hour working day that costs many lives and caused far more injuries and people forced out of their jobs - a fight that took many decades.
It's very easy to ask people to not be "divisive" when you're the one with the money and the power, and not the ones who have the rights they have now as a consequence of the deaths and sacrifices of people being "divisive" by daring to stand up for themselves.
[1] https://en.wikipedia.org/wiki/Triangle_Shirtwaist_Factory_fi...