Oh, I don't know.  Tattoos can have their uses.  In Egypt the Coptic Christians frequently tattoo their infant children with a cross - a tiny cross on the forehead or on the wrist. Why?  So that, if the child is kidnapped by Muslims, that child will still know that  he or she began life in the Christian community. 

And in Australia a murder was solved because of a tattoo.  A woman's foot was found washed up on a beach, still sufficiently well preserved that a distinctive tattoo (I think, a design of a blue rose) was clearly visible.  The police broadcast the image of the tattoo far and wide.  As a result, they were ultimately able to match the foot to a missing person; the identification was clinched with a DNA match between the kin of that missing person, and the foot; and so, once they knew exactly who had gone missing, when and where, they were able to track down and catch the murderers (it turned out to be murderers).  If the murdered lady had not had her foot tattooed, the detectives' job would have been a good deal more difficult.