Most users are interested in FRED® and not ALFRED®. In other words, most people want to know what's the most accurate information about the past that is available today (FRED®) not what information was known on some past date in history (ALFRED®).
Note that the FRED® and ALFRED® web services use the same URLs but with different options. The default options for each URL have been chosen to make the most sense for FRED® users. In particular by default, the real-time period has been set to today's date. ALFRED® users can change the real-time period by setting the realtime_start and realtime_end variables.Related: FRED®, ALFRED®, Setting Real-Time Periods