system administration functions with hardcoded superuser checks

There are some system administration functions that have hardcoded
superuser checks, specifically:

pg_reload_conf
pg_rotate_logfile
pg_read_file
pg_read_file_all
pg_read_binary_file
pg_read_binary_file_all
pg_stat_file
pg_ls_dir

Some of these are useful in monitoring or maintenance tools, and the
hardcoded superuser checks require that these tools run with maximum
privileges.  Couldn't we just install these functions without default
privileges and allow users to grant privileges as necessary?