Hi Dingle,
Sorry to hear you're having problems with CCBill. They are actualy quite easy to work with and their customer support is spectacular. You should cut them some slack as clearly this support person did not understand what you were asking him.
I see what you mean though. I personally have never trusted any sites that ask me to log-in with my ccbill u/p. I'm sure its safe, but who knows? I got into the habbit long ago of going right to
http://www.ccbill.com and logging in from there.
Good luck with CCBill!