With Wake and CP3, a player who idolizes CP3 will be using the CP3 Locker Room. Some guys like that there is a strong connection between their chosen role model and themselves. Also, CP3 isn't just another player. He is head of the Players' Association and a multi-time NBA all-star.
And yes, CP3 does stop by Wake campus from time to time, so there is a much greater chance of a guy running into CP3 on the Wake campus (CP3 grew up not far from it) than there would be if he went to say Stanford. And that "running into" could also include playing pickup basketball and ending up in each other's contact lists.
In my profession, I was honored and thrilled to meet some of the people who wrote the text books I studied from. I was even more thrilled when I, as a young professional, got to know personally the people on my "professional Mount Rushmore" and we each had a card in the other's Rolodex, back in the day.
These teenagers are dreaming of careers as professional basketball players. CP3 is one of the most respected players in the NBA. Why not do everything you can to connect with him, including going to college where he did?