Earlier quoted context omitted.
How did you know that XorNot replied to your previous comment? Notifications, addictive design and gamification are really bad practices that we should try to avoid - but the underlying drug of social media is that someone noticed and reacted to your content, and HN provides that just like Facebook or Twitter.
Most people on here and Reddit are lurkers. They still keep coming back even though the see no tasty upvotes.
I turn off notifications on my phone for almost any app. It's just way too annoying. I'll get to it when I get to it! I guess I'm part of that minority mentioned above but as you say I do keep coming back too. It's not black and white but we can stay on the healthy side.
If I try to find an analogy, it's the difference between sitting by the fire in the evening and chatting with other people vs. spending the entire day running around listening to and actively spreading rumors.