tons of emails and calls trying to get donations
That's what I was going to say.
Inspector already covered most. (show off)
Insurance (guns, life, others)
NRA Training courses
Publications
They appear to support shows and publications
I always find it interesting that NRA courses always focuses on safety, safety, safety. Rightfully so. But that I see lots of stuff on shows like American Rifleman (the Official Journal of the NRA) that violate safety rules. Having completed numerous NRA courses, they always have "the NRA way", which frankly sometimes I disagree with, but you have to do their way to get the certification.
I wasn't aware that one needed to be NRA RSOs to be ROs at Koko Head. Maybe one needs to be there, but I know a few ROs that work there that aren't NRA RSOs.