From what I see, the successful website like Amazon and Ebay also act like ad posting website, even though people call it an e-commerce site. So perhaps, CraigsCoin can expand in the future, to be a blockchain commerce (b-commerce) platform, where end users do business just like with e-bay today.
And what would the advantage of a blockchain-based approach for this be? For ads, which require no physical inventory & delivery, this is a good idea. For eCommerce though I doubt it.