Imagine the following scenario:
Some kid wants to join a discourse site about games, Unicorns, bomb making or whatever:
"Mommy, can I have your credit card details so I can join this website?"
We both know what the answer will (or should) be.
Have you considered a scenario where the payer can go to PayPal, enter some info and pay the membership, and the profile/site just includes "Amount, source type (CC, PayPal, applepay), date, level"?