What is the industry standard for outfitters who refer clients to a hunting operation? And if they refer a client one year, do they get reoccurring commission on that client if he returns. And how about if that client brings family or friends or refers others to come, does outfitter get payments on them as well, kinda like a pyramid scheme? Thanks in advance.

"Outfitter" is an extremely loose term, open to broad and varied interpretations. If you're referring to international hunting, it can be some dude that went to South Africa once, the operator said that he'd give him a discount on his next hunt if he referred someone, and all of a sudden he's an "outfitter"/broker, carnival barking for you to accompany him. There's been one or two on here. They usually don't know their butt from a hole in the ground, but they're gonna try to come off as Harry Selby himself.

In the states it could mean anything from a real joker to a hard-working western operation with a stable of horses and mules, equipment, etc.

I doubt there's any "industry standard" whatsoever.

Outfitters run the hunts, booking agents and the like refer clients.
Pretty sure if you just recc them to someone you're not getting anything from the outfitter.
Folks on forums do that all day long.
If you want to start a booking agency you might get some compensation from outfitters. There are lots out there now though.

10-20% depending on several factors