Evan Schuman's StorefrontBacktalk

Realistically, the coupon program is a side effect. This approach is really a way of following customers around—or leading them from one retailer to the next.

Visa says it plans to expand the service, now that it has worked the bugs out with Gap. And why not? The hard part is tracking the customers who have signed up for the program. Sending mobile coupons is trivial—and better still, a text message doesn’t require a smartphone. Adding more retailers just means having to decide which retailers’ offers to text to a customer or possibly calculating where the customer is likely to go next.

Visa is also in a position to offer Google-like services, such as restaurant recommendations—except that Visa knows everywhere a cardholder eats using the card, what restaurants a cardholder has stopped eating at and how much the cardholder likes to spend, so it has much more complete data for making suggestions.

And Visa is even in a position to offer non-retail services to cardholders, like sending reminders to head for the airport when a customer has bought a plane ticket using the card—but not sending a reminder if the customer already appears to be at the airport.

What about other location-related services? If Visa can stalk card-using customers just as effectively as Apple or Google when they’re out shopping (but without leaving a lot of location data on a smartphone, the way Apple and Google do), how long will it be before Visa starts identifying the shopping patterns of consumers and selling that information to retailers?

That’s a long way from interchange. But it may be Visa’s unavoidable future. Market leaders tend to stick too long with the business model that took them to the top. Visa has been spreading investments around in the mobile-payments space (for example, with Square, Ecrio and Monitise), but it’s pretty clear that—like everyone else—Visa doesn’t know what will eventually gut its interchange business.

Retailers love the idea of a serious competitor that will force interchange rates down. It hasn’t come along yet. But Visa certainly believes that, sooner or later, it will.

The irony is, the card company may not have to wait. If it can make enough from location-based services, Visa might actually be able to squeeze out competition by reducing interchange rates in exchange for services that retailers actually appreciate. If that happens, Visa will have gutted its own interchange business.