Grrr. None of this (article or most of the comments) has much to do with Haskell. It applies to all languages, right? You implement an abstraction using an appropriate data structure, accounting for the frequency of various operation you plan to perform. Often a list will be the wrong data structure - no big surprise.

But if you'd like to implement a stack, perhaps with a lot of elements, then a singly linked list is a reasonable choice. But you need to think about the operations you need. If you're just pushing, popping, looking at the top element, checking for empty, then great!

If you need to check the length, then you'll need to keep a counter, otherwise you'll pay O(n) time. If you need to make a copy for read-only purposes, great, constant time. If you need to make a copy for destructive use, then you'll have to pay O(n) time. This is all Mom-n-apple pie.