I'll just say, right now this is a no. We shouldn't be taking new members for granted, they owe nothing to us and if we shun them they'll just leave (and they rightfully should if that's the case). We should welcome them, help them become accustomed to the place, and let them feel like they belong, not treat them as a lesser member. It just wouldn't benefit a community of our size.
Only communities that could safely have something like this is one that's either elitist in nature or one that is so large that no one would be familiar with all other active members. One of that size will normally have a fend-for-yourself attitude, in which case a forum like this suggestion can be encouragement if implemented properly... but not in a case like ours.