I know what you mean, AND it's just a part of a tool developing a patina through use. Learn to love your machine for what it is to you, not for its box fresh perfection. This is my MacBook; though there are many like it, this one is mine etc.
If you sit at a desk, put your MacBook on a stand and use an external keyboard when you can; otherwise there's nothing you can reasonably do. I used one of those rubber keyboard skins for a short time, but it detracted so significantly from the experience of using the computer that it was completely self-defeating.