I did not see the word surrendered in your examples.
The undefended city of Chambersburg "surrendered" but still refused to pay the ransom demanded, so it was burned, again.
You're leaning too heavily on that word "surrender", FRiend, and it won't hold the weight of your case.
The truth is, the Confederacy had fewer opportunities to practice "scorched earth", but they did it on occasion, and long before Sherman marched into Georgia.