How do you know it wasn't necessary? Have you asked the man involved what all the possible alternatives were? Does it normally feed on dead animals? Are there cords behind the stand that it could have chewed through? Did he have an important meeting or anything to get to soon after and couldn't afford the time to empty the fish tank and move the stand or leave it there until he gets back?
Because captive STOs eat dead meat just fine. Do the research. He even comments that that they don't need live mice!
Important meeting? Wow, now you're really stretching here. Considering the trouble he went to to tie a string on a live mouse, wriggle it around and record all of it... says a lot really.
You're assuming he gets a kick out of it, insulting him and others who agree with him. Getting all emotional doesn't win arguments (nor does the "I'm right, you're wrong" attitude).
If you watch his other videos of live feeding, you'll understand why I am saying he's doing it for kicks. He has animals who he feeds live, that absolutely do not need live food in captivity. The disclaimer he puts on these videos (this is like the Discovery channel, don't call this cruel or else I'll delete your post, etc) says a lot too. The people who agree with him... well... essentially they're saying "yeah, let's put an animal through unnecessary anguish and risk the pet to bites, scratches and parasites at the same time". And most of the people who do, are saying how fun it is, laughing at the misfortune of the prey animal, etc. Nothing more than a "canned hunt", really, to entertain himself and the mass of drooling "haha pwned" idiots.
In addition, read a couple of his own comments in the video and you'll see he is having a laugh about it too. Need I say more?
Here's another one of his videos:
[video=youtube;vZpULn_3M7s]http://www.youtube.com/watch?v=vZpULn_3M7s[/video]
Perhaps you'd like to explain to me why this person would be adding classical music to a live feeding video if it wasn't for entertainment? You seem to be saying I am making quite a few assumptions, but so are you from the looks of it. What's worse is that you're trying to justify this kind of behaviour? From the horse's own mouth:
"They do make great pets. They don't NEED live mice to live." Thus, not necessary at all, thus... a questionable motive.