My point isn't really specifically about monoids; they're just an example of what often goes on in Haskell, which is that people put theory before practicality and mathematical (and hence often esoteric) definitions before practical, real-world definitions. Like I've said a few times, this isn't incorrect at all. Nor is it surprising given Haskell's origins, nor is it without purpose since it deepens your understanding of what's going on in the language. It's just a simple fact that the mathematical jargon is a turn-off to newcomers and those who don't feel they want to be forced to learn math while they're programming, or might think they're incapable of doing so.
As it turns out, I'm not one of those people; I love the mathematical side of Haskell and I love that I've learned what a Monoid is and developed an interest in type theory, category theory and all kinds of other things. But not everyone is like that, and that's the point I'm making.