Many of the prices we pay seem to make little sense. We shell out $2.29 for a coffee at Starbucks when a nearly identical brew can be had at the corner deli for less than a dollar. We may be less willing to give blood for $25 than to donate it for free. Americans hire cheap illegal immigrants to fix the roof or mow the lawn, and vote for politicians who promise to spend billions to keep them out of the country. And citizens of the industrialized West pay hundreds of dollars a year in taxes or cash for someone to cart away trash that would be a valuable commodity in poorer parts of the world.