In my fields, the Tippy Top programs aren't the ones that prepare people to be professors. Indeed, becoming a professor is often considered a third-rate choice. It's ok, but only if one is basically a research professor in a position comparable to the research professors running the program. For those folks, classroom teaching is not a primary activity and is seen more as a pesky chore that is a good trade-off for complete research freedom, unlike a national lab or industrial lab where one must work on the "right" projects.
Teaching as most professors know it is not a valued activity and people coming out of those programs definitely will be much better prepared for life as a research scientist or engineer, not a professor. Professors come from the good programs that see value in teaching.
Graduates of Harvard or MIT in economics aren't typically going to the Federal Reserve or World Bank as their first pick and there aren't many post-docs either. A SLAC is unlikely to be a first pick either of course, unless people decide they want to teach more, but the good ones (e.g. Williams that I was looking at) are loaded with graduates of these elite programs. I suspect this is a bit closer to what happens in the humanities than in your field.