Maybe we are talking about different abstractions. Perhaps libraries? I reimplemented (probably badly) session handling code in wsgi (python) - because the Django code was over 2000 lines long and used other libraries and I did not understand it - especially when all I wanted was to store a 128bit number in a client cookie and then look it up when I saw it again.

So the idea is simple (cookie sessions) but the different ways of implementing it can hold complexity, errors and abstractions.

There is nothing stopping the same happening with Haskell - I can I am sure write terrible code even in the best languages (see my entire output for proof :-)