yes, that is normal behavior for the directory template.  The directory template was designed to be used as a resource listing, for example a directory of businesses, web sites, contacts, etc. So the template does not include a file upload token. 

 However, it's easy to add by editing the template.

1) make a copy of the /Templates/Directory folder and paste it in the same location, rename it as /Templates/DirectoryWithFiles (or whatever you want)

2) edit the form.html template file and add a [FILE] token whereever you want it. Easiest way is to copy the URL tablerow, paste it and change the prompt text and token

3) edit the Template.html template file and place a [DOWNLOAD] token whereever you want it to be

4) go back to your repository and select the new template in the module settings

If you have any questions or problems at all, just ask

its working now thanks.

I still needed to enter something in the Resource URL field (even entering 'none' worked ok).

but I decided to remove the Resource URL field from the form.html file altogether.

I find that this now works better as a News list than the Announcement module (as you can have content organised into several pages).
 
What would be ideal though - is to make the 'upload a file' button optional (i.e. for the occasions when there is nothing to upload) - but i don't think this looks possible?