They are linked directly to a checking account so you are paying with your own money.

VOA: special.2009.05.21

Linn now tries to get more information about this blocked linked account, but gets nowhere.

FORBES: How Amazon Can Make Your Kindle Content Vanish -- And Not Give You A Reason Why

My Coinbase account is linked to my bank account.

FORBES: Living On Bitcoin For A Week: The Journey Begins

Users open a PayPal account linked to a credit card or a bank account.

ECONOMIST: Internet firms