Pro-discount purchasing on all your gear is a nice perk.
When I was VERY active with SAR teams, I used to keep very good records of my expenditures - gear, meals while on SAR missions, mileage, etc.
I had so much mileage logged in a contemporaneous, hand-written notebook that my accountant didn't want to claim it: He said that claiming that much mileage would trigger an audit.
We don't do SAR for the perks....