Frequently a skin will attract 'the idiot element' and receive comments one would 'rather not' have.
With the size of the site it's nigh-on impossible for an admin to catch all of them in a timely fashion...so the trick is to email an admin/moderator for 'aisle cleanup', or if all else fails a quick 'request' for same on the Forum or IRC.
Once 'dealt with' the forum thread can be removed as well....problem solved.
What is less than 'successful' is to engage in boisterous banter with the 'problem' person as that only attracts more unwanted comment.
Some are definitely less adept at snuffing out these issues and actually do more harm than good.
Like grafitti, it's best 'cleaned' promptly....