Good info! Dan Bowling is on to something.
Law schools tend to attract competitive types, and if those big name associate jobs are the ones everyone is gunning for, that trend can perpetuate itself, and smart people can end up fighting for something they might not really want.
This is purely anecdotal, but a lot of the people I knew from law school weren't super-happy at the huge firms. Some of the ones who stayed got less happy (and became bigger Associates).
Most of my college friends who went to law school and ended up in BigLaw hated it after a year or two. Most of them ended up going to smaller firms, two went into public service, one went in-house, and three left the profession altogether. It sounded brutal.