It depends on the section for me. If it's in RPG sections then I don't care. If it's in Intelligent Debate or something then it can be annoying since those topics generally die out for the reason that everything's been said and then somebody just comes and goes 'Oh, and this is what I think' without realizing that it has all been said before and it was a total waste of time for anybody to read.
I also dislike it if it's totally off-topic.
Also, in a lot of old topics, the members that were posting are now inactive, and so there's absolutely no reason to post in the topic since you are responding to people that no longer exist in any way relevant to this forum.
But in general, a lot of people are annoyed by it likely just because they think it's cool to be annoyed by it or they like to minimod.
Also, your signature makes people want to derep you.