axlryder said:
It's important to you and the majority of the human race because you've developed to need it. If one is never held as a child, they may grow up to have an aversion to physical contact. They might have a poorly developed mirror neurons and such. The point is, once they've developed past a certain point, it becomes ingrained into their psyche. It's no longer an abnormality to them, it's who they are. I'm not saying this is a good thing, but that doesn't make them "sick in the head" as you say, merely different from you or I.
To be completely fair, "sick in the head" is a colloquially term for strange and eccentric behavior. The definition of strange or eccentric: "not normal". Thus, someone behaving differently from the average is sick in the head. It's not really a negative.
Also, using the whole "normality is subjective" argument is completely ludicrous. Normality is, by definition, the average state. There's no such thing as subjective normality. For example, your everyday routine is familiar, but if it involves randomly punching strangers in the dick, it's certainly not normal. Confusing the terms doesn't help anyone.