Even reputable news sites often only check that the e-mail address you have given is valid, but make no effort at all to verify that you are who you claim to be online.
So when e-commerce sites, spawned by the new commerce revolution, are blacklisted for deceiving web users and reputable companies by directing consumers away from their initial choice to sites that pay them advertising fees, it impacts the credibility of the system and jeopardizes the system as a whole.