That's not necessarily true. There's nothing to say that this wasn't an intentional stunt to push Prime Day to the front of various deal websites by selling camera equipment to professionals as a loss leader.

The size of Amazon is such that they can afford to bleed heavily from selling mid range pro camera equipment at a significant loss whilst recouping the profit from all the incidental purchases and traffic that the attention brought.

I'm not saying that this is what happened, but marketing budgets run into the millions (especially for a highly promoted yearly event like Prime Day) and dropping a few hundred thousand on a scheme like this isn't so outrageous.