What feature distinguishes American Express from other card issuers in its early days?

The distinguishing feature of American Express in its early days was its dual capability of both issuing cards and acquiring merchants, which allowed it to collect detailed transaction data effectively. This unique structure gave American Express a competitive edge as it could manage the entire transaction process, providing insight into customer spending behaviors and patterns. This capability not only facilitated a better understanding of the market but also allowed American Express to tailor its services and rewards to meet customer needs more effectively.

While other options, such as rewards programs, travel insurance, and contactless payments are features of various card products today, they did not define American Express's early differentiation in the market. The card issuer's comprehensive data collection ability laid the groundwork for its later offerings, which would leverage this rich data set for innovative consumer benefits and improved customer experiences.