Index: head/etc/defaults/rc.conf
===================================================================
--- head/etc/defaults/rc.conf
+++ head/etc/defaults/rc.conf
@@ -741,3 +741,9 @@
 		done
 	}
 fi
+
+# Allow vendors to override FreeBSD defaults in /etc/default/rc.conf
+# without the need to carefully manage /etc/rc.conf.
+if [ -r /etc/defaults/vendor.conf ]; then
+	. /etc/defaults/vendor.conf
+fi