Group and Role Disagreement

Fellow Hackers,

Given this SQL:

BEGIN;

CREATE ROLE foo WITH NOLOGIN;

CREATE ROLE foo_bar WITH LOGIN PASSWORD '***' INHERIT IN ROLE foo;

CREATE ROLE foo_baz WITH LOGIN PASSWORD '***' INHERIT IN ROLE foo;

CREATE ROLE foo_yow WITH LOGIN PASSWORD '***' INHERIT
IN ROLE foo, foo_bar, foo_baz;

SELECT groname, array_agg(rolname)
FROM pg_group
JOIN pg_roles ON pg_roles.oid = ANY(grolist)
WHERE groname IN ('foo', 'foo_bar', 'foo_baz', 'foo_yow')
GROUP BY groname;

SELECT r.rolname,
ARRAY(SELECT b.rolname
FROM pg_catalog.pg_auth_members m
JOIN pg_catalog.pg_roles b ON (m.roleid = b.oid)
WHERE m.member = r.oid) as memberof
FROM pg_catalog.pg_roles r
WHERE rolname IN ('foo', 'foo_bar', 'foo_baz', 'foo_yow');

ROLLBACK;

The output is:

BEGIN
CREATE ROLE
CREATE ROLE
CREATE ROLE
CREATE ROLE
groname | array_agg
---------+---------------------------
foo | {foo_bar,foo_baz,foo_yow}
(1 row)

rolname | memberof
---------+-----------------------
foo | {}
foo_bar | {foo}
foo_baz | {foo}
foo_yow | {foo,foo_bar,foo_baz}
(4 rows)

ROLLBACK

My question is: why is the group membership of the foo_bar, foo_baz, and foo_yow roles not reflected in pg_group? Should it not have the same associations as pg_roles? A quick query shows that the only record in pg_group is for the "foo" group -- it doesn't even know that the foo_bar, foo_baz, and foo_yow roles also act as groups. Should it?

Thanks,

David