In SEDIV, or maybe it's just Atlanta Region, you get free entry to a Solo 2 for every two days of volunteering. I'm not sure which specialties qualify, but I think all of them.
At some tracks, the club will get discounted track fees when they provide workers for other events (I think Charlotte used to do this, I hear Barber does, also Cal. Speedway, others?). VIR seems to have a great relationship like that with NCR. So in those cases drivers do benefit from working events.
If they pay attention while in the station, drivers can learn a lot while working. Like watching how their competition takes corners where they're faster.
I'm a licensed F&C worker, and have worked several years now. I started when I decided to start back racing after a 10 year absence. I would recomend it to anyone who wants to see how the other guy drives.