Apple kind-of charges you the one dollar, though they don't really charge it. Has something to do with checking availability of funds. I don't know exactly how it works. It is not uncommon for your bank to show this as a $1 charge, followed hours, or (rarely) a couple of days latter, with a refund.
This is how Apple makes sure you've given them valid and active credit card information.
You will not actually pay them anything for registration.