&gt;<i>Here too, the cream colored background looks gorgeous on paper and just weird and out of place on a webpage.</i><p>Sounds like a case of habit. Or would you say Hacker News background color look weird and out of place too?  
To me it is easier on the eyes, but more importantly having white as an accent color is useful to emphasize or separate graphs and figures from the main text.<p>I can&#x27;t agree more with your general point though. Mindless copycating is a plague.