There is an explanation as to  why ticking Add Docs will also get you Add Folders permissions.  

This is so because O-DL allows you to add .zip files and unzip them.  These .zip files can contain directory structures as well as documents.  When a directory structure Is found, it is re-created under the folder you are uploading the .zip to.  So, in order to enable unzipping of folders, we have to give add folder rights.

If you wanted to disable this behaviour, you'd have to modify  the javascript that regulates it.


The file that has the JS is found here:
DesktopModules/XSDocumentLibrary/JavaScripts/xsutils.js



The original javascript function is this:

function addDocCheck(oThis,sViewId, sAddId, sEditDocId) {
        if(oThis.checked){
                document.getElementById(sViewId).checked=true;
                document.getElementById(sAddId).checked=true;
                if (document.getElementById(sEditDocId) != null) document.getElementById(sEditDocId).checked=true;
}




You would have to modify it like this:


function addDocCheck(oThis,sViewId, sAddId, sEditDocId) {
        if(oThis.checked){
                document.getElementById(sViewId).checked=true;
                document.getElementById(sAddId).checked=true;

                /*comment out the following line */
                /*if (document.getElementById(sEditDocId) != null) document.getElementById(sEditDocId).checked=true;*/
}



You should also disable the unzip functionality in the upload pane.

you can do so by setting the unzip checkbox attribute of the chxDocumentUnzip enabled=false in the

DesktopModules/XSDocumentLibrary/Components/FileUploader/XSFileUploader.ascx file

<asp:CheckBox ID="chxDocumentOverwrite" Runat="server" Checked="true" class="xsBox95" enabled="false"></asp:CheckBox>