Wheel Bearings on a 7 year old pop-up - Shuld I?

I clean, repack , check the brake shoes about twice a year. Moisture has an effect on the bearings as well as miles and sitting can and will cause the grease to harden. I also have a set of bearings and seals already packed and ready to install if needed.I figure that would be better than having to leave the PUP, boat trailer etc. along side of the road while looking for parts. Of course this is my opinion and my method.