Are Signature Pads Dangerous to Privacy?

WildHunter asks: "While making a foray into a local retailer today I paid using a credit card and was asked to sign a paper receipt on top of a digital pad. Being cautious I asked what it was for and I was assured that it was 'fully secure and safe to use'. Being a typical paranoid Slashdotter I offered to sign off of the pad but refused to sign on the pad. Was I over reacting or can someone back up my paranoia with some facts?" Think about it, some deceitful vendor has one of these, sells you something, gets your signature, and can then ring up loads of charges on your card using a digital copy of said signature over, and over, and over... you get the idea. Do the current crop of signature pads prevent against this and other similar kind of deceit?