I used to think that when I first started and asked a similar question. However, I realized that I was counting total views and not impressions. When I counted impressions my data tallies up with my analytics more or less.
Another problem is the differences in what your analytics counts as the start of the day versus what hubpages counts as the start of the day. I have no clue when the start or end of the day is for hubpages, as the stats are on a 24hr rolling clock.
I'm not sure if this helps or not as your question didn't explain which stats you were specifically referring to but hopefully this helps.