Bad analogy...R-rated films are only intended for a specific audience thus will make less money, the only exception I know of is Passion of the Christ.
I got the impression that “300” was bad, too violent, explicit, etc. I liked it very much when I finally watched it. It is violent, explicit and cruel but the message was outstanding and to me that is the strength of this movie. The objectionable things didn’t at all distract. The men’s muscular development was also something to behold and I learned that they had a special workout to get that way.
Shrek, Alvin and the Chipmunks and Ratatouille were intended for a specific audience also.