IMO bitbills is a bit premature, because of the huge flactuation in value. By the time you print 1 BTC bills and ship them, they might be worth 10-20 times their worth, and suddenly consumer are out to buy 0.1 BTC bills instead.
.... why not just have it all electronic ?
I guess I'm trying to find out how my grandma and millions like her who are computer illiterate can easily buy bitcoins. Bitbills are the easiest way.