Code:

@EventHandler
public void onInteract(PlayerInteractEvent e){
        Bukkit.broadcastMessage(e.getAction().name());
}

When opening a door from directly infront of it, it broadcasts "LEFT_CLICK_AIR".
However, if you angel your camera downwards, so that if the door wasn't there and that there was a block behind the door, it would not be LEFT_CLICK_AIR.

If you click where the doors rotators are, it doesn't do LEFT_CLICK_AIR either, so I'm mainly thinking this is a minecraft bug, and it thinks that the window part of the door is air, and since the player is doing the left click animation, its assuming that the player must be left clicking.