The interaction at the jail was part of Reacher's persona and from the books. Of course, it is not realistic. One thing that turned me off the books was exactly that, as mention - MPs are the great martial artists of the military, blah, blah. The show isn't as obnoxious as the books. I've already said this, Reacher's life style is presented as a warrior wandering the land, etc. From my lane, it is extremely pathological.