Working Documents and Final Published Documents

We have a restricted-access 'Policy Admin' SharePoint site where the original Word documents are kept and maintained. The primary library contains all the Word documents with a number of columns showing things like Review Date, Status (in the review cycle - we have about 20 options), Owner, Business Area, Subject Area. This allows the Policy team to keep track of them.

Once they are finalised they are saved as PDFs and copied to our current intranet where users access them. I am never quite sure why people want to turn Word documents to PDFs when the former are stored in documents with read only access and you can even prevent downloading. Users can still download and modify PDFs if they can be bothered but they can't change the version in the intranet policy library unless they have permission to do that.