they can withhold. The rationale — ostensibly — is to save money, staff-time and paperwork; the effect is to keep the public uninformed about bureaucratic decisions. Any Presidential candidate who’ll change this anti-public policy gets my vote.
The Weekly Compilation of Presidential Documents is the official record of Presidential statements: transcripts of speeches and press conferences, nominations and appointments, proclamations, etc. Also includes some details about the President’s daily schedule, and a cumulative index of topics addressed in his public statements (very handy).