Google is continuing to make it easier to use their cloud service Drive as your every day storage system. As a means to this end, Google has introduced a new website button called "Save to Drive." This new button, when implemented on websites, allows a user to easily save a file to their Drive, rather than download it to their local system.
Unfortunately, the button still relies on your local web connection. The file is first downloaded to your local system and then uploaded to Drive. This means you can't avoid uploading a large file on a slow upload connection or on a metered mobile connection. In an ideal world, the file would go directly to your Drive.