I agree with the observation that Am. Goldfinch retire early.
They also are late risers too, by the way (pure IMO science).
Cardinal, Junco, and White-th. Sparrow, are all at the feeders
before - and after -  the Goldfinch. 
Another entire Order are "early to bed, late to rise":  woodpeckers.
Off subject:
I added Dark-eyed Junco to the "visit the suet" category today
during this winter weather. 
Good birding,  Larry Herbert, Joplin, Jasper Co. MO.  [log in to unmask] 
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