After thinking about this more, I think you're wrong. There are at least two purposes to voting. One is to help find better comments, because points are associated with the comments.
But the other purpose is to provide karma to the posters. Otherwise there would be no accumulation of points associated with posters and shown next to your name when you're logged in.
Past 200 it doesn't matter. There is no extra functionality that gets enabled, so it only is an odometer telling you how much work you could have done.
But the other purpose is to provide karma to the posters. Otherwise there would be no accumulation of points associated with posters and shown next to your name when you're logged in.