[michaelt]

  I don’t know and I can’t explain it.

Have you, by any chance, seen most of these conversations happening on the internet?

It's my experience that you can say something 99% of people agree with, the 99% don't feel the need to reply with their support. But the 1% who disagree do feel the need to say so. And forums will validate this, with upvotes for well-reasoned discussion (i.e. disagreement), and downvotes for 'me too' comments.

If you posted "The bald eagle is a majestic creature" I'd get downvoted for replying "This! You tell 'em" but I'd get upvoted for replying "Bald eagles are much smaller than wedge-tailed eagles, and they have a call so sickly film makers use the call of the red tailed hawk instead"