That's part of the joke. Lots of devs keen to do Haskell, so market forces reduce the pay of such jobs, especially if they are not expert in nature (typical back/front end stuff). Yet you get someone who took the time to learn Haskell.

I watched some great videos from India Haskell meetups, which gives me the impression you can go to one of those and get "cheaper" developers. Not saying they'll work for odesk rates but certainly could be cheaper than a cubicaled SF worker.