Why did we kill Osama bin Laden rather than take him as a POW?

I understand about him refusing to surrender but why did we not shoot him in a way that would not kill him but rather disable him and take him away? I think we could have possibly got a lot of good information from bin Laden if we did not kill him on site. After all the information was gathered we could have got back at him and tortured him like he deserve. Being shot in the head is a much faster and almost painless death which is something bin Laden did not deserve.