As a luxury of being so small, this community encourages all sorts of questions and discussion...but without karma. Compare the boost 'Ask HN' posts get on HN; HN has to either encourage or discourage discussion; its size makes it hard to do much else.
I made one Ask HN post that didn't get a single comment. Surprising how a community a tiny fraction of the size can be more responsive in some ways.
Maybe that shouldn't be surprising though, since responsiveness tends to be inversely proportional to size in so many things [1]. When there are many people using the site it's tempting to think, "Well someone has got to respond to my post!" But there is much more posting happening on large sites too, and different rules emerge (e.g. HN culture's greater emphasis on karma, as you suggest).
[1] Committees, web browsers, vehicles, mammals...
