If there are no replies, then most likely nobody knows the answer or they are biting their tongue because if you had searched the wiki, forum, or google, you would find the answer.
1) In the case that no one knows the answer, the person may assume that the lack or replies is due to the information being easily available and go on a fruitless frustrating search.
2) In the case that the information is easily available the person may have looked but overlooked it. They may assume that no one knows the answer and be frustrated by the lack of support.
Either situation drives people away from the community which I think is a bad thing. I guess the way I see it, a harsh RTFF answer is better than no answer. At least then you identify that the information does exist and you eliminate the possibility that no one knows the answer.