Most payment gateways provide no name-based authorization - a fake name will work just fine.
Having signatures match is just one straightforward kind of evidence that you agreed to the contract.
I am curious though which biometrics will eventually replace the signature, especially with so many transactions online where I can spend thousands of dollars without signing anything.
http://www.americanexpress.com/us/content/prepaid/gift-cards... http://usa.visa.com/personal/cards/prepaid/gift_card_faq.htm...