Insult generator in Haskell

Insult.hs

{-# LANGUAGE DeriveDataTypeable, QuasiQuotes #-}
module Main where

import Data.Char (toUpper)
import Data.List (intersperse)
import Data.String.Interpolate (i)
import System.Environment (getArgs)

main :: IO ()
main = getArgs >>= putStrLn . makeInsult

-- Actual generator
makeInsult :: [String] -> String
makeInsult [] = makeInsult ["dumbass"]
makeInsult (word:_) =
  let insult = map toUpper word
      remaining = filter (not . (`elem` insult)) ['A'..'Z']
      spaced = intersperse ' '
  in [i|#{spaced remaining}

You must be wondering what happened to the rest of the letters
.
.

They are written below
.
.
.
.
.
.
.
.
.
.


#{spaced insult}
|]