Tyler Cowen, who directs GMU's Mercatus Center, has a short essay at Crooked Timber about law and economics, with some interesting points. Here's one:
The eighty-page “blah blah blah” law review article is harder to sell in an age of competitive professionalization of the law professor market itself. Law and economics arguments usually can be stated succinctly and the quality of argumentation and evidence is relatively easy to evaluate. It is possible, for instance, that an argument or piece of evidence is wrong and can be demonstrated as such. If law and economics requires some technical knowledge, so much the better for its ability to “signal” the quality of law school professors. I expect these trends to continue.
In a later section, Tyler notes there is a marked difference between market-oriented economists and market-oriented lawyers, primarily in their political framework but also substantively in their regard for written constitutions. In both senses, the average economist is less constrained.
My own experience confirms that for economists, there is much less of a ladder towards judgeships and the ultimate occupational pinnacle represented by the Supreme Court. Perhaps you could argue that being the Federal Reserve Chairman is the pinnacle, but there is no calculable path to that position as there seems to be towards the SC.