"Base 8 is like base 10, really... if you're missing two fingers.
"
And there ya go, except for one small detail. One of the fingers has to represent zero in Base 8. That's a problem if you count on your fingers.
Which finger do you use to represent 0 in base 10? If you don't need it in base 10, you don't need it in base 8 either.
But that's why God gave us belly buttons.