[treeder]

I think you missed most of the points in the post. To address your points which are well covered in the post (I'm guessing you didn't read it):

1) Printing bills is very expensive 2) Credit card payment networks are also very, very expensive (2.5-3.5% or more of every transaction) 3) Billions of people can't get credit cards. 4) How do you send printed bills around the world?