I've noticed that too. These comments are in the same category as people complaining about being downmodded; they don't make very interesting reading. Perhaps I should put something in the site guidelines about them.
Even more concerning to me is how frequently these "not hacker news" comments are added to posts that are off the beaten track (i.e. not about code, startups, and such) but which I find genuinely interesting. The last thing I'd want for this site is diminished diversity. I don't like the spam or bait posts either, but I'm glad you haven't cracked down on them in a way that triggers this other, imho more significant risk.
Edit: while I'm at it, the "not hacker news" noise belongs to a more general class that I've been training myself to tune out, which is the "meta hacker news" category. A bad day here is one in which there's more discussion of the site itself than anything else. And yes, I'm fully aware that I'm doing it right now. :) But I've been resisting it successfully for weeks...
Meh. I had really meant the above post to be a sarcastic satire of the 'this isn't hacker news' posts you all just mentioned. Sorry, I suppose it sounded different in my mind.
Edit: while I'm at it, the "not hacker news" noise belongs to a more general class that I've been training myself to tune out, which is the "meta hacker news" category. A bad day here is one in which there's more discussion of the site itself than anything else. And yes, I'm fully aware that I'm doing it right now. :) But I've been resisting it successfully for weeks...