mk-ultra - that picture obviously does not represent most cases of feeding live. The point of showing an EXTREME is to prevent whatever-it-is (in this case live feeding) so that extreme doesn't happen again. If you were trying to dissuade someone from leaving a 20ft snake with a human baby, you would have to point out the rare occurences that a snake has attacked/constricted a child. Obviously that's not the norm, but it happens, and to prevent it one must point out extreme cases.
Of course, you probably have the best method of feeding live (supervising and so on), but why take the risk? Just because there has never been a bite to you or the snake, does that mean there never will be? That's like people who don't dust their bugs. They say "well my lizard is still fine - if he starts to show signs of MBD then I will start dusting his food." Of course, if the snake WON'T eat f/t (after many tries for f/k) then one obviously has to resort to live. But I have the feeling that many "give in" sooner than they should - when they are steps away from converting their snake to f/t/k.