I upvoted you, but I strongly disagree with that I actually am using those in Haskell (knowing that you did not say that but merely point out what was said).
In the theoretical sense OO and FP share some concept like encapsulation and polymorphism. But a class in C++/Java/Ruby is whole other thing then type-classes in Haskell.
I think what the person you're replying to is saying is you actually are. You don't literally write "Foo x = new Foo()" but that's just a syntactic feature of some language. Haskell has types and classes and sub classes. You just don't write them the same way.