That's exactly what closing duplicates does: cross references it to the original. If someone wants to post new information, they can do it on the original.
An alternative to shaming is that you could just accept this great new content that a volunteer is giving you.
Whenever a question gets a new post it gets bumped up to the top of the activity again - the same amount of possible attention as when an hour old question gets a new answer too.
What it really comes down to, though, is that when somebody asks a new question, I want to answer their new question, with all of its subtleties, in response to its particular phrasing, in its context.
Edit: In fact, I should admit that I usually only put the effort into answering old questions when it's something that has a lot of views. It's an indication that the question is linked somewhere prominent or is ranking well for some search terms. Those questions are worth putting the time in for. Most aren't.
Closing with a link to the original is cross-referencing in a way that does just the opposite: It decreases the vitality of the community by taking away opportunities for newcomers to take part in the gamification feature.
Let's frame the issue another way: What's Stack Overflow really for? Is it for people to ask questions and get answers? Or is it just a gamified Wikipedia?