You show them that they purchased a service, IP and email, then you show them that they accessed the service, and you win the dispute. I have no issue with Paypal doing this. You must demonstrate to Paypal, to win, that they are the person in question and they did access the service they purchased, i.e. their history of pages they viewed, posted upon that require the service, additional features they used as part of the service, etc. You only need one.