Drag and drop multiple files from desktop - Forced to resize every image?

When I drag and drop multiple images (all 1280x720) into a PSD set up to be 1280x720, why does the resulting image on the artboard start out as 960x340?

Why can't I get PS to just leave files of a matching resolution alone and not force me to transform every single image? It's okay for one or two images, but when I'm dropping in hundreds of frames to build a comic book, it becomes not only annoying, but a huge waste of time!

Am I missing something simple here?