I'm the person responsible for administering the server that powers this open archive. The type of data you mention is being included in the archive when ever possible. Further, the research group I work for has existing specific open data efforts in multiple fields including, and beyond, computer science. For example, today I'm working on setting up an architectural open access archive with the staff here that will include CAD files for humans and semantic web triple store data for search engines.
I couldn't find any data/code associated with non-CS papers, across a quick sampling of US DSpace systems -- although most of the submissions seem to be from the back catalog.
No offense to DSpace, but adequate systems for publishing open data have been available for twenty years, i.e. an ftp site. It will require a top-of-line mandate from institutions or journals to make it happen.
BTW, the archive system software is open source: http://dspace.org/