“Reuven buys a car from Shimon for $3000. Total wealth is increased because both transactors have more wealth than they started out with, Reuven has a car that he wanted more than he wanted the $3000 and Shimon has the $3000 that he wanted more than he wanted the car. “
No wealth increased in that transaction. UTILITY increased, but the car is still worth just $3000.