We all know Cooper, Fletcher, Smith, Baker etc are occupations which have been used as surnames for generations. So how come Cobbler is never used in this way?
There is also Draper, Coleman, Gardner, etc, I don't know anyone called Cobbler, probably just as well as there a few connations with the name!
I suppose if you were called Cobbler you could change it to Shoemaker, There is a jockey called that name!!
And a German racing-driver or two, spelt - in their case - Schumacher!
In addition, there is certainly a Cobble - minus the final r - in my local phone-book.
still doesn't really explain why the name is so uncommon, though. My guess would be that there were lots more bakers than cobblers (a town might have lots of bakers but only one cobbler)... but that's just off the top of my head.