Presumably to balance out the canned soup sodium in the rest of the box.
EDIT: Thanks to Jennie in the comments for deciphering some of the card for me!
From a box sold in San Antonio, Texas.
No Salt Herb Mix
3/4 c. dried basil
5 Tbsp. dried oregano
3 Tbsp. EACH dried thyme and garlic powder
1 Tbsp. black pepper
2 tsp. EACH allspice and coriander
Mix well. Store in air-tight jar. (Shake before using)
Use 2 tsp. / 1 c. rice or barley