[gozucito]

At first, I laughed.

But it's a good question. My answer is social contact sharpens our mind. Without it, we would be stupider. And God knows we're stupid enough as it is without degrading our intellectual faculties further.

At a basic level, loners will get hunted down by tribes because they are easy prey and because their behavior can be misconstrued or spun by grifters as nefarious because they are different.