Benefits of a C & R are discounts from most major firearm parts and accessories sellers (Midway, etc.), you can buy straight from a C & R Firearm wholesaler like Southern Ohio Gun -AIM Surplus - Classic, etc at close or on their wholesale prices. Say your local gun shop decides to sell imported M-1 Carbines, they'll pay close to, or exactly what you'd pay for it from SOG. Plus, you get it shipped straight to your house.
Mine comes up for renewal this year, I've saved a helluva lot more than the $30.00 issue price I paid to get my C & R license.