That's because they haven't made them for (who knows...).
It's just a compressor though - You set the attack and release the way you want them (this one has an "auto" function if you want), set the ratio the way you want it to react and the threshold down where you need it to work.
As you'd probably expect, no one can just "tell you" how to set those controls - It needs to be done live on that system.
If you're just looking to "whack 'em" pretty good, set the threshold at around 4:1, use the "auto" and "interactive" settings for the knee and the A&R, then have someone scream into it continuously while bringing the threshold down to a point where you're seeing several (6?) dB of gain reduction.
Or, you can use a ratio of 1.1 or 1.5:1 with a much lower threshold and ride the complete dynamic range of almost anyone.
Or, you can use a ratio of around 6 or 8:1 and severely limit the dynamic range of the loudest people.
Or, Or, Or...