Personally, I've never really understood this mindset too much ultimately. Sure, the person could easily search through the thread to find out they're answer more often than not, but there really isn't any harm in asking, and perhaps coming back later to get the answer to their question if they prefer. Its kind of similar to the whole debate behind someone who would go to a forum to ask a question, rather than try and google the answer, the only difference here being the latter is usually a far more straight up and surefire way to get your answer, as opposed to times on forums requiring you sifting through a few pages, though the search function *generally* manages to alleviate that problem. Either way, not that it really matters much on here from what I've seen, but I'd say generally the best answer is either to simply ignore them if you don't know, or answer it if you and feel like it, both ultimately just kind of detract from the real point of a thread discussing a game in the first place, and yes, I realize the irony in me posting something that has VERY little to contribute to the thread of this game right now. Really, I'm just kind of surprised to see it pop up in my search as updated after so long since having seen it last.
Ultimately though, point being, both kind of detract from the purpose of a forum/thread dedicated to a game to begin with, and one solution tends to solve the problem pretty quickly and efficiently, while the other tends to just drag out something that generally adds very little to the thread to begin with. The idea behind it might be sound, but the execution is rarely something I see being done for the right reasons, or with any real benefit to the topic at hand.