Huh, I must be an anomaly since I start counting at the thumb as opposed to the index finger. It just makes more sense that way. Somebody mentioned something in the comments that I would like to echo, and that's that the analysis of the French language isn't entirely correct. To say "eighty" in French you would be saying "quatre-vingt", or four-twenties. Similarly "ninety" is "quatre-vingt dix" or four-twenties ten.

I wonder how these numeric systems or lack thereof are related to a languages evolution from classical languages, such as Hellenic languages.