In an ideal world there would be a moderator that would be able to shut down/consolidate a thread when another existing thread has been presented. In another ideal world, this conversation would have been started in the existing thread to begin with. It works out better for OP because there is already a lot of existing information to work from, plus the higher post count makes it more likely to be viewed by more people, PLUS anyone already subscribed to that thread will be ping'd about a new post. So, overall it's better for someone to continue an existing thread than it is to start a new one. The "flaming" is due to a lack of active moderatorship on this sub-forum, where all the "same group" of active members can do is point someone in the right direction versus recreating something that has already been made but could be added to.
The only time that a "zombie thread" bash happens is when someone resurrects a thread that died for a good reason (beating a dead horse, off-topic banter or arguing, etc) and the poster is bringing it back to continue the same type of conversation that made it die in the first place. If that makes sense.