I do. When I think of algorithms I vaguely imagine DAG, which maps nicely to S-expr (the junction point maps to a tail function call).

In languages with syntax, I have to add syntactic fluff to satisfy the compiler, which is mostly an extra annoyance.

I don't say my way of thinking is the correct one. Some great programmers I respect have said they don't think in DAG (and naturally they choose languages other than Lisp as a primary tool).

Most humans don't. Some do.