Did people ever volunteer for gladiator duty?

You know, some Roman is unemployed, no prospects, a little suicidal but decides, "Why waste a healthy body like mine with suicide when I could become:
I) a hero or
II) dead, which is what I already want.

Anyone?

They sure did. In fact, it was apparently quite common, according to this:

3 minutes ! ? !

Dang You’re fast!

I’ve heard gladiators described as the “rock stars” of their time. Not only did many volunteer to be gladiators, but many slave gladiators continued to fight even after they won their freedom. The emporer Commodus even went into the ring himself, a story that was thoroughly mangled in typical Hollywood style by the movie Gladiator. You can find a much more accurate description of Commodus here: http://www.roman-emperors.org/commod.htm

On Commodus in the amphitheatre, Gibbon is, as usual, too good not to quote:

So not exactly life-threatening as combats went. And, inevitably, Gibbon saves the best jab for the footnote (*), which begins: