paypal.com fees is interest or this is consider as service fee.

There is a website paypal.com on which if somebody send you money through credit card they(PAYPAL.com) will charge from receiver of money 30 cent +2.2% of the amount send to receiver also they will charge you more if the money is send to you and you are in other country than U.S.A. .Is this come in interest or this is there fee as you are using their website for sending and receiving money. NOTE: They charge money from the guy who receives the money not from the sender. The link for fee rates conditions are below http://www.paypal.com/cgi-bin/webscr?cmd=_display-fees-outside