Age 15 used to be when you lost your virginity, now you're not even allowed to kiss. For the boy it was his first kiss, and you figure he's at least her age or maybe a couple years older. Think about it -- a junior in high school who's never been kissed. He was apparently encouraged by the counselors and high-fived afterwards, which makes him sound like one of the guys, and the girl who got kicked out was evidently drawn to him.
So it's not like he's never kissed because he's some repulsive outcast type. Youth culture is so neo-Victorian these days that even an average or somewhat above-average guy must wait until 11th grade for his first kiss.
The camp has no religious affiliation; it's in liberal Massachusetts and appears to cater to parents along the Bos-Wash corridor. So it's not as though it's conservative Christians trying to clamp down on sin. The owners are more concerned about their reputation and the response of all parents, so their actions reflect more on the attitudes of the average well-to-do liberal parent who sends their kid there. "I'm not sending my kid off to the type of camp where..."
Helicopter parenting is an across-the-board change. Parents of different political orientations offer different rationalizations, of course -- liberals focus primarily on preventing harm, conservatives add in the protection from corruption. At the end of the day, though, everyone has become an over-protective weenie parent, and kids from all backgrounds are growing up stunted and awkward because of their lack of social experience and connectedness.