I also like being able to keep up with comments, although it's more than that. I feel like I'd be letting down my readers if I just ignored their comments, whether it's a matter of saying "thanks" or responding to a criticism. I can see how writing would be quite different in this respect if the author were overloaded with commenters.

Indeed, this might be a point where the greater popularity would go to the writer's head, since eventually the writer would no longer be able to think of her readers as individuals. They'd become a disembodied mass.