I explain to Paul Krugman Why He's Wrong.

[osewalrus]

Paul Krugman asked what problem cryptocurrency solves. I explain to him that just because credit card companies shift the transaction costs (and monopoly rent seeking) from consumers to merchants does not mean they magically go away.
http://www.wetmachine.com/tales-of-the-sausage-factory/what-problem-does-cryptocurrency-solve-ask-any-small-business-or-the-collins-family/ ;