This might not be of common use within a Git repo, but non-text files are displayed as byte stream in the the text editor.
I tried to open an image file and the bytestream is displayed as text rather than an (inline) image.
When opening a zip file, the same happens. Here I would expect an download dialog or some file information (size, contents) and a download link.
That thought had crossed my mind about images, but I hadn't considered zip files. Okee doke, need to make I handle a bunch of different file types. I suppose saying "Don't open these files" won't get the job done ;)