A number of internet forums have branched off from HN to fill niches that HN doesn't fill. I'm beginning to think that somebody needs to fork a forum for Schadenfreude. We don't want comments like this here.
Just imagine if you will if all members of the site created similar comments constantly. That would hide all of the discussion relevant to the topics being discussed.
But, I agree with what you said- I don't like it when people enjoy suffering either. I just think that possibly the best way to handle it would be to just ignore those posts, as you might elicit more response from them.