Many of the French don't bathe, wear deodorant, or wear underwear. 'Cologne' is used to mask their poor hygiene.
A lot of Americans don't either. Except many of them don't even bother to wear Cologne.
Also, is this a fact or just your conjecture? Have you lived in France? Are there studies that prove this?
Actually it is, from my personal experience, true, but that doesn't change the fact that you didn't tell us the basis for your argument.