I know I'm a n00b, but I do have some experience in other groups that have dealt with similar sentiments (i.e. the past was much better, who are all these newbie idiots, etc.).
Restricting the forums to donors only and such is not really a good idea (at least the whole forum). The problem is that when you start making new people feel unwelcome, they go away. And if too many new people go away, the entire site will die of attrition.
In the SFS club I was in, the older students took an overbearing "elitist" attitude. They figured that new people suck and treated them like dirt until they got older. This caused that club to have an average membership of about 12, with freshman often joining and then leaving after only a few months as members.
Then, new officers came into power with the attitude that everyone who could play and have fun was cool. Now membership is insanely high (it's one of the larger groups on campus) and they do a lot more things.
The point? Treating newbs like dirt weakens the organization, because you have to replenish those who you lose through regular attrition to keep the community healthy. Having a donor only chat (in addition to the donor only comic showcase) is viable, though, since you encourage people to become donors (money for Brad = good) and you have a place where only regulars can post, while still keeping a place for new people to introduce themselves. You need a mechanism for getting to know the new people so the best of them can advance and be made to feel accepted, otherwise, again, you fall into the atrophy model.
