.. what? This is a really weird take. Amazon isn't gonna put random swastikas on stuff. Contracts they have with media companies probably specify in what ways and to what degree they can alter images. I have no doubt they did this legally; WB asked them to change it, they didn't issue a legal demand.

Contracts often have a lot of wiggle room for stuff like this, and the reason life isn't 24/7 lawsuits is because parties with a grievance talk to each other and reach an agreement without going to court and invoking legality.