'pkg_delete -c pfresolved' (random example) certainly omit the
"You should..." hints and deletes the "_pfresolved" user/group
automatically, but the manual only hints at one pkg_create(1)
annotation:

     -c      Delete extra configuration file, mentioned as
                   @extra file
             in the packing-list.

I'm not certain what else -c does (for various pkg_* programs),
its description should be complete and pretty without its own line:

     -c      Delete extra configuration files, users and groups mentioned as
             @extra, @newuser and @newgroup in the packing-list, respectively.

This is a start, perhaps.
Feedback?


Index: pkg_add.1
===================================================================
RCS file: /cvs/src/usr.sbin/pkg_add/pkg_add.1,v
diff -u -p -r1.168 pkg_add.1
--- pkg_add.1	2 Oct 2024 09:14:08 -0000	1.168
+++ pkg_add.1	23 Nov 2024 22:10:26 -0000
@@ -309,7 +309,7 @@ as the prefix to prepend to any object e
 .It Fl c
 While replacing packages, delete extra configuration file in the old package,
 mentioned as
-.Dl @extra file
+.Cm @extra
 in the packing-list.
 .It Fl D Ar name Ns Op = Ns Ar value
 Force installation of the package.
Index: pkg_delete.1
===================================================================
RCS file: /cvs/src/usr.sbin/pkg_add/pkg_delete.1,v
diff -u -p -r1.59 pkg_delete.1
--- pkg_delete.1	10 Jul 2018 10:20:51 -0000	1.59
+++ pkg_delete.1	23 Nov 2024 22:08:54 -0000
@@ -97,9 +97,12 @@ Set
 .Ar pkg-destdir
 as the prefix to prepend to any object deleted.
 .It Fl c
-Delete extra configuration file, mentioned as
-.Dl @extra file
-in the packing-list.
+Delete extra configuration files, users and groups mentioned as
+.Cm @extra ,
+.Cm @newuser
+and
+.Cm @newgroup
+in the packing-list, respectively.
 .It Fl D Ar name Ns Op = Ns Ar value
 Force removal of the package.
 .Ar name