offenses and defenses are more complex than "I got number 37! Ok, I got number 1!" It doesn't work that way. College offenses scheme to try and take advantage of all this. And, players make mistakes, which occasionally result in the type of easy TD that we got with Hill. It was a great play design and great call. It may have been a mistake by a defensive player, or it may have been a hole in their scheme or just that particular defensive play call.
But your characterization of how college-level defenses work is not accurate at all.