Perhaps there's a market for higher denominations on the cheapest possible material.
It does seem that if delivery of a physical product mitigates the risk of accepting Paypal/Credit Cards enough for companies to do it, that just mailing out private keys on paper ought to be sufficient for people who are just trying to buy bitcoins to have electronically. It seems the same thing to me, of course, but perhaps the fact of whether or not there's a real "coin" involved actually does make the payment companies look at it differently somehow.
