NO it isn't. If you are going to hunt any type of animal for the meat, you have to bleed it out right away or else the blood will coagulate in the meat and render the meat useless. Whether hunting with a gun or bow and arrow, that's the way it is, PERIOD.
So, they were either out killing deer just for the heck of it with no intention of field dressing it, which is killing for the thrill or they had a knife on them but decided to strangle it to death just for jollies and capture the joyous occasion on film.
YOU may not see the reason so many see this as contemptible, but either way it is. So to you it may be much ado about nada, imaginations working overtime, etc. but to those of us who know better, it's much more than that. What kind of a hunter doesn't carry a knife?