People go to nature to interact with nature, not with traces of other human beings. You don't want to ride 4 hours to countryside only to find very same things you've been running away from.

In contrast, people go to blogs to find opinions, and traces of opinions of others are usually adding, not subtracting. One can say whole HN is a sandbox for sharing opinions, therefore "untouched" posts with no comments and low points are less attractive.