As a user, if I ask for a DOC I want a DOC. If your service gives me a zip, it's not what I asked for. As a programmer, this is quite simple to solve as others

As a user, if I ask for a DOC I want a DOC. If your service gives me a zip, it's not what I asked for. As a programmer, this is quite simple to solve as others have said how (store gzipped and serve with correct headers).