The Norgren valves in the suspension system should be exercised. This is especially true if there is any moisture or humidity in the system because the aluminum valve body can corrode and eventually the valve will not shift to open or close as intended and it can begin to leak. Bottom line, allow it to work for its intended purpose.
As to using it in a campground not all sites are level so make use of it, but even on level sites use it to lower the coach so getting in and out of the coach is easy due to the lower step. Lowering the coach also is sure to enable you to bang your head on the awning rods, something we all do and have the scars to prove it.