I suspect it would be would intuitive to you as you're not thinking it's a document of an application, rather a document that can be produced by many applications.
Being intuitive is subjective. Let's say 'consistent'. This is an interesting one because Photoshop is one of the few, like an Illustrator EPS, that does allow you to save as another format. However, most don't. Apps produce docs in their format. If you want it in another format you have to export it as something to which it isn't.
However, opening a jpeg and Save As a jpeg would be intuitive to me too. And yet, opening a .doc into Apple Pages then saving as a .doc wouldn't be intuitive because I'm used to how Apps work. In the image world we've had it easy with all these compatible formats.