In most cases, the receipt that came with an electronic device is adequate for returning the device for replacement under warranty, so the registration card accomplishes little. The information on the card may end up for sale to marketing companies.
There is an electronic toothbrush that offers a warranty six months longer if the consumer registers the product with the manufacturer, according to Consumerist. Also, the card gives the manufacturer the consumer's contact information if the product goes through a recall. However, the possibility that lists of names may be for sale to marketing companies means that people should check to see if registration offers any tangible benefit.