I, too find it odd that that they would characterize wide noodles as “regional” within Shaanxi since they are so closely associated with Xi’an, the capital and by far the largest city of Shaanxi. Maybe the noodle maker is from or from near Shanxi province, known for hand-pulled noodles and shaved noodles etc. but no wide noodles.
Incidentally, Thousand Tasty’s Chinese name (仟佰味肉夾饃) means “Thousand tastes roj jia mo.” Did you try the rou jia mo there?
