Making an eXmerce sale is no different from a cash or credit card sale except for the form of payment. Once a member is identified as an eXmerce member and it comes time to make the sale, you simply accept your new customer’s eXmerce card as payment. The eXmerce dollars will immediately be transferred into your account for you to purchase from any other member.
No academics I talked to were aware of any evidence that barter was actually the precursor to money, despite the story’s prevalence in economics textbooks and the public’s consciousness. Some argue that no one ever believed barter was real to begin with—the idea was a crude model used to simplify the context of modern economic systems, not a real theory about past ones.