Have you ever witnessed this procedure done? I have. My son was circumcized and he cried as much as he does when he is hungry, he stopped crying when it was over and he rarely cried when his diapers were changed. Is there an increase in infection, yes, but this is minimized if the incision is carefully protected. Not to mention, that you are wrong about anesthesia. Embla cream can be used, which is a xylocaine cream administered before the procedure.
I speculate, with little research to support me, again only speculate, that due to the infants underdeveloped cognitive state, pain is not the same as that of an adult. I have witnessed infants with serious burns that would require narcotics for an adult and the child barely cried and was otherwise happy and healthy.
Are you saying that this is the only procedure that we do which inflicts pain on infants? What about ear piercings? Is this not "unnecessary" pain? The main point is, does it really make a big difference in the long run? Is anyone really "hurt" by such procedures?
It is purely a personal choice, but from the vehement howls from the anti-circumcision crowds, too often I hear very emotion laced rhetoric, not science. There is statistical evidence on their side, but when I hear such arguments as "decreased sensitivity", "mutilation", "not whole", etc. it diminishes their argument.