 We explain what rewards card programs do with your information. Meet Mary and Kevin. Last time they went shopping at the supermarket, they signed up for a rewards card program. That way, every time they shop for groceries, they collect points that they can exchange for discounts or rewards. But what happens in the background when they're at the cash register and present their card? The supermarket doesn't manage the points themselves. Actually, they hire another service provider for that and pass the information to them. So the supermarket sends them details about where and when Mary and Kevin have shopped, how much they've spent, and with some service providers, even what they've bought. While the couple are pondering whether to exchange their points for a coffee maker, discounts, or something similar, the card provider is analyzing their data. It sends the results back to the supermarket. Because that way, the supermarket can send Mary and Kevin targeted advertising and plan future campaigns to keep the two of them shopping there as often as possible. Here's what Mary and Kevin ought to know. Each time they shop, they leave a trail of data behind. If they use the same card in many stores, that paints a very detailed picture of them. Do they go to a lot of concerts? When do they buy groceries? Where do they go on vacation? And so on. For that reason, many rewards programs allow you to request a report on which information a value is stored. Also, Mary and Kevin can often opt out of certain details being collected and of receiving advertisements. Now they both know what happens to their customer data, and that way they can make a better informed decision about whether or where to use their card from now on.