An example can be found under this answer, where a discussion based on "My main purpose of being here is in collecting the votes. I'd even go further and say that this is my main purpose in life." is going on (I guess for fun), but personally I had to consume some of my time until figuring out that these somewhat upvoted comments were totally unrelated to the answer.
So it cool to have these chats under posts, or should they strictly limited in chat?
I thought no, but the number of the upvotes in these comments, made me ask, so that I know when to flag a comment or not in sites that I am experienced in (e.g., Stack Overflow), in future cases (without putting more unneeded work in mods).