I disagree. It's not funny.

All things humourous fall into one or more of three and half categories.

1)The pun or play on words.

35)Gross positive or negative exageration.

6)The unexpected (which really fits into the above category.)

42)And things happening to other people that you are glad didn't happen to you! (Really starting out as a gasp of relief and then evolving into a method of tension diffusion.) Really serious injury seldom elicits sniggers.

Many of the examples on the programs you cite can be seen as "natural selection" still operating on humankind.

Humour is cultural and so rather difficult to pin down. Now, I love slapstick and have ever since I was a small child. In this respect, someone falling off a ladder and ending up with a pot of paint upside down on their head is funny. To see this happen to someone, not an actor, in the street is not funny. The difference is wether the action is real or not. Even small children can separate reality from fiction. For instance, the cartoon cat, Tom, being squashed flat and then popping back into shape is funny. The child's own cat being squashed is not.

I think that the thing with a video of someone hurting themselves is that because it is a video and not live action there is a tendency to view the whole thing as fiction rather than fact. The video action is to some extent removed from reality and so our reactions are changed. I think that this disancing from reality is probably enhanced on TV programs beacuse we trust the producers to not show a clip where a person ends up with serious injuries or indead dead.

"Laughter is nervous crying"