Complex sentence: The doughnuts proved so popular the Salisbury, North Carolina Krispy Kreme location, in the town where Cheerwine is made, sold them as well, and after July 31, this was the only place to get them.
Split into simpler sentences: The doughnuts proved so popular, the Salisbury, North Carolina Krispy Kreme location (the town where Cheerwine is made), sold them as well. After July 31, this was the only place to get them.