WSJ:

As more third-party sellers have signed up to offer products through Amazon and use its order-fulfillment services, the Seattle-based giant has allowed many to pool their inventory with supposedly identical items supplied by other sellers—in essence commingling products from third-party merchants with those supplied directly to Amazon by the brands themselves.

In other words, a product ordered from a third-party seller may not have originated from that particular seller. If the bar code matches, any one that is on the shelf will do.

The implication here is that you might order a brand name product and receive a knockoff instead. I can’t imagine that Amazon isn’t working on a fix for this.