Common Lisp, unlike Scheme, was always a language designed for professional programmers not students. Its big symbols contain values, functions, and property lists to improve performance - lumping all those together with a single pointer and offsets saves a few bytes of memory and reduces the garbage collector's workload. Like destructive list manipulation, it's not expressing some Computer Science theory; it's there because sharp knives are useful.

In terms of the importance attached to language aesthetics, ANSI Common Lisp is probably closer to PHP than Ruby, ML, or Python. That doesn't mean that it isn't used to write beautiful code, only that it leaves doing so solely to the programmer's discretion.