ALTER ROLE/DATABASE RESET ALL versus security

It looks to me like the code in AlterSetting() will allow an ordinary
user to blow away all settings for himself.  Even those that are for
SUSET variables and were presumably set for him by a superuser.  Isn't
this a security hole?  I would expect that an unprivileged user should
not be able to change such settings, not even to the extent of
reverting to the installation-wide default.
        regards, tom lane