locals clearing bug?

leak.clj

;; support code
(defn heap-mb 
  "Report approx heap size in megabytes."
  []
  (System/gc) (System/gc)
  (quot (- (.totalMemory (Runtime/getRuntime))
           (.freeMemory (Runtime/getRuntime)))
        1000000))

(defn mb-seq 
  "Make a non-chunked seq of n mb-sized elements"
  [n]
  (for [i (take n (iterate inc 0))]
    (byte-array 1000000)))

;; the function in question
(defn consume [xs]
  (loop [ys xs]
    (doseq [x ys]
      (println (heap-mb)))))