Well it's true, the parent might regret the lack of AP credits more than the student, if the parent is the one paying tuition.
It's not just that though. He was on snowboard cross and tennis teams and built a pretty strong core of friends in that time period.
The summer before senior year I sent him to Spain to study Spanish. (I had considered Japan but that would have been more of a vacation than a learning experience. He got a 5 on the Japanese AP test without ever having taken a class.) Ironically he got a poor score on the AP Spanish test his senior year so those three weeks didn't really help with that but he had a great experience nonetheless.