I think sometimes it is that, people will say 'why didn't you just do a search on the forum to see if you can find the answer you are looking for. Then in their search, they find a posting and still have more questions so they post on the old post.
I see this in other forums as well - and I have actually seen people who have been on the forum for a while actually yell at the 'new' poster for not doing a search first. So to keep from getting snipped at, some of us look for old posts first and that is how more questions get put on old posts. I've seen older/longer forum members actually say things like 'that question was answered way back when - do your homework, we are not answering it again - and in the meantime.... well ya know!