Why doesn't a haircut hurt?

A pinch and much more a cut on a finger hurts. A strong tap on the head also hurts. Why doesn't a haircut hurt?

 Here's a fact : Almost your entire body is covered with hair, though much of it is so fine that makes it barely visible. The hair grows from some 5 million follicles, of which about 100,000 are in the scalp. The hair is already dead by the time each hair emerges from within each follicle. No amount of hair tonic or any wonder cure can revive it.
Our scalp hair usually grows on average of about 12 - 15 centimeters or 5 to 6 inches in a span of one year. It keeps getting longer, even though its dead. These older, dead hair cells are being pushed out by the new hair growth. Cutting the dead hair doesn't hurt, but you'll cry out in pain when your hair s pulled from the root.

Reference: Reader's Digest Why In The World