When I go to the local home improvement store, they have a funny little 'signing' process they make me go through.  They want me to 'sign' on one of those checkout pads when I use my credit card.  Apparently, this prevents people from stealing my card and using it without my permission.  Nice idea, but nothing they do prevents this theft.
When I try to 'sign,' either the pad is slippery, or the surface so scratched, I cannot get anything to look remotely like my signature.  That does not appear to matter!