Additionally, the GS1 DataBar carries a much wider range of information specific to the product that the coupon is to be used for. The older UPC uses a system of "family codes" to help the register determine which item or items the coupon can be scanned with. However, this system has unfortunately been abused, both accidentally and intentionally, by shoppers. With the old family codes, the register checks to make sure that the product purchased falls into a matching family of products made by the manufacturer. But in many cases, more than one product may be recognized as a "match" for that coupon if the product also happens to be part of the same family. This left the door wide open for coupon abuse.
For example, let's say you have a coupon for a box of cereal "16 ounces or larger." When you get to the store, you grab the 12-ounce box by mistake, use your coupon ... and it scans just fine! Whether you intended to or not, you've just committed coupon fraud. You have used a coupon on an item it wasn't specified for. Mistakes like this occasionally do happen.
Where UPC family codes become a real problem, though, is when people intentionally abuse the system by trying to determine what other (often, completely unrelated) products they might be able to use a coupon for. One of the most flagrant abuses came to my attention via a story detailed in a popular coupon blog. People supposedly used $10 coupons for teeth-whitening strips to buy baby diapers. The same company made both of these products and the coupons intended for whitening strips successfully scanned when a shopper purchased diapers instead. If the shoppers were successful in slipping their coupons by an unsuspecting cashier, they fraudulently enjoyed huge savings on diapers instead of the whitening strips.