Why does this program consume 8.6G memory?

Hungry.hs

module Main where

import Control.Monad (replicateM)
import Data.Char (ord)
import Data.Foldable (for_)
import Data.List (foldl')
import Data.Word (Word)
import System.Environment (getArgs)

hash :: [Char] -> Word
hash = foldl' step 0
  where
  step acc c = acc * 31 + fromIntegral (ord c)

compress :: Word -> Word -> Word
compress modulus = (`mod` modulus) . (* 11)

chars :: [Char]
chars = ['a'..'z'] <> ['0'..'9']

strings :: [[Char]]
strings = replicateM 6 chars

main :: IO ()
main = do
  (modulusArg : _) <- getArgs
  let
    modulus = read modulusArg
    cond = (== 42)
    collisions = filter (cond . compress modulus . hash) strings
  for_ collisions putStrLn

replicateM 6 chars is the culprit. The cause is something like: builds the (very large) sublists and holds on to them due to sharing while it performsliftA2 (:) c sublists