What is the type of person likely to be attracted to languages like Haskell or Clojure?
On one hand, Haskell or Clojure probably attract more academic types who have a reputation for (consistent with my experience) on-average worse-quality code.
On other hand, the barrier-to-entry for these languages is higher so they tend to be programmed by more experienced folks. I assume that people pick functional languages in part because they believe the functional paradigm leads to higher-quality code, so the sample probably cares more about code quality to begin with.
They went to school, they where not bashed in the head with hammers.