Because they are obnoxious, and they smell real bad. I also have a French last name, but I was born in Georgia.
I have old French blood too. Nice to hear someone with whom I can finally tell my horrible ancestral sin. My ancestor who fought in the Revolutionary War (a high level Hessian who fought for Britain, was hated by the Germans because of that, and became a government official in the U.S.) married some French lady. And I and all my siblings have the same middle name. deKrafft. From, Baron Von Krafft and ____ De la Mitre. :( But after those 200 years, I'm more or less pure Southern :)