The short answer is maybe.

In 2013, AdAge had sources tell them that data was available to target groups of credit card users (rather than at an individual level).

They also reported:

The information supplied by credit card firms and other data companies like Acxiom is arguably more reliable because it reflects real consumer purchases as opposed to inferences about what people appear to be interested in. The majority of behavioral data used to target digital ads has its share of problems, suggested the trading desk source who said people might be added to audience segments (think in-market shoe buyers) based only on a one-time site visit. In addition, some computers in homes are used by multiple people, muddying behavioral profiles.