But economies are generally built on the exchange of what is scarce. We have a money economy instead of a dirt economy because money is harder to get than dirt.
Attention certainly seems to be in short supply.
Sometimes, of course, the economics metaphor gets carried a little too far. Goldhaber argues, for example, that attention will eventually replace money in the economy. This new attention to attention is neat stuff. The trouble is, we in the corporate information systems biz are still acting as if information is the scarce item. I'm guessing that this heavy focus on attention-demanding data has something to do with the fact that most of it is never turned into information or knowledge.