query: SELECT T1.City_Town FROM Addresses AS T1 JOIN Customers AS T2 ON T1.Address_ID  =  T2.Address_ID EXCEPT SELECT T1.City_Town FROM Addresses AS T1 JOIN Performers AS T2 ON T1.Address_ID  =  T2.Address_ID
question: Which cities have at least one customer but no performer?
query_toks: SELECT T1.City_Town FROM Addresses AS T1 JOIN Customers AS T2 ON T1.Address_ID = T2.Address_ID EXCEPT SELECT T1.City_Town FROM Addresses AS T1 JOIN Performers AS T2 ON T1.Address_ID = T2.Address_ID
query_toks_no_value: select t1 . city_town from addresses as t1 join customers as t2 on t1 . address_id = t2 . address_id except select t1 . city_town from addresses as t1 join performers as t2 on t1 . address_id = t2 . address_id
question_toks: Which cities have at least one customer but no performer?