This certainly isn't the first time someone has exploited the phone system and stuck another with the bill. Maybe it's time for the phone company to get their fraud detection and prevention services at least on par with what the credit card companies have done.
As long as the customers are responsible for the charges, they have no business reason to invest in fraud protection.
Bruce Schenier refers to this as an externality, and had written about it a number of times in the context of credit card security and computer security.
http://www.schneier.com/blog/archives/2007/01/information_sec_1.html
http://www.schneier.com/blog/archives/2006/03/credit_card_com.html
http://www.schneier.com/blog/archives/2005/10/preventing_iden.html