> As he says, a tightrope act is just as difficult at any height. The only need to make it dangerous is because the audience wants the circus.

Tho, only a few of the people who engage in these dangerous sports are famous or earn money on that. As in, if you look at those sports, there are always people who seek the danger and possible self destruction. They do it, because they want to do them. Not because of the audience.