Uhhhmmm....Steam is not that right? Where do I put steam DRM? Will there be an extra field?
I think that Steam DRM can be considered as physical protection because it requires an input which is not hard coded into a disc and is not made available within a package, not like serials for example.
One media which "cannot" be run without an other media.
Or you can just rename the field back to normal and tell certain people not to add CD-Checks and DVD-Checks as protection