Nine times out of ten when I do that, I'm providing a link to a question that has been previously answered in that thread.

That's why you'll see Linkie or Reference before one of those links.

That way the person who is asking the question can see the discussion or the explanation in regards to their question.

if someone else has already answered the poster's question, why repeat the answer?

edit: Maybe instead of taking the time to insult another player, maybe you should take the time and try to help out?