Never even thought of it. Just someones personal reaction to a very postive emotional situation. I notice lots of people laugh when they are nervous. Even the "pros" on the video admit to being nervous all the time. Perhaps this is just that release. They get a little more wound up than the average hunter I believe as well. They have to wait a lot longer to pull the trigger so they get good video and clear camera angles. The knot just keeps getting tighter and tighter the longer they wait and some people just explode. I was in shcok after my first kill and just mumbled "wow" all the way out of the bush. When I was halfway home at a red light it really hit me and I let out one of those primal screams followed by the 2 hour perma-grin.
After thinking about it I don't think there is any problem with it and I don't think they are showing disrespect.