I did not mean to claim that they do not. My claim is that "much of the functional..." So, referring to things like cons lists is easy, though that one is old. Look at the multitude of pointers in any of the purely functional data structures, though. There is a lot of overhead in building up these structures.

Look into the Scala (and clojure?) vector sometime. Literally a 32-ary tree. Makes the algorithm somewhat pleasant to look at, but are we really shocked when something using a simple array can beat it in performance?

Now, it is a perfectly fair and valid point that optimizing development time may be preferred. We are allowed contradictary valid points in situations that are trade off defined.