[[ http://www.gnu.org/distros/free-system-distribution-guidelines.html | FSDG ]]-free systems are forbidden to "steer users towards obtaining any nonfree information for practical use, or encourage them to do so."
[[ https://www.debian.org/social_contract#guidelines |DFSG ]]-free code, doing same same functions but different without non-free stuff available, is arguably not FSDG-free.
E.g. a tool favoring non-free fonts over free fonts for rendering text arguably (albeit rather quietly) promotes the use of said non-free fonts.