We're human. We learn and bond through touch. When a baby cries, it's not enough to just speak to it in a soothing tone - you generally have to pick the baby up, cradle it, rub its back, etc. When we see a dog or a cat, the first thing kids want to do is pet it (and most adults, too). When we're feeling lost or alone or overwhelmed, many of us get into the "I just want a hug
" state of mind. We're very tactile. And you know what? It doesn't matter if it's nature or nurture (probably a little bit of both, given that most cultures seem to have conversational touching but different cultures are more touchy than others, and yes, there was a study done on it), because these kids are still being nurtured in much the same way at home. Unless there's a huge counterculture movement from the school and whatnot, they are still going to learn those mannerisms, which means that banning touch is isolationary. Whether it's necessary or not depends on the severity of the injuries at each school, I suppose.