Exhibiting or displaying crucifixion victims was, no doubt, an important part of the public phase of punishment, both as a perceived deterrent to crime, disobedience, rebellion, etc. and as a means to humiliate and degrade the person condemned to death. Even in cultures where male nudity was acceptable, primarily in sporting events, the sight of a stark naked man, tied or nailed to a cross, must have been shocking. For the casual spectators I imagine it would be more curiosity, coupled by a prurient interest in being able to watch. For those who might have suffered harm from the condemned, feared or disliked them, it would have been a form of closure and the ultimate pay back. The longer and more horrible the victim's suffering the more justice would be meted out, in their minds. Of course, the helpless man, hanging naked on the cross, was oblivious to anything but the inexorable approach of death.