OSS vs. Non-OSS repos

It came as a surprise to me to read that openSUSE wants to set up an
online repo for non-free packages, as said repository has been there for
some years now:
http://download.opensuse.org/distribution/1x.y/repo/non-oss compared
to
http://download.opensuse.org/distribution/1x.y/repo/oss where all the
open source goodness is.

The only place where free and unfree software are mixed is the
installation DVD. So an easy way to have a guaranteed free-software-only
system is to just use the oss online repo and remove everything that's not
there.