Please help! Alaska itinerary for RV newbie.

At the risk of further exposing my novice self, I have a basic question -- If you stay multiple days at a campground but want to take your RV to visit nearby sites (or store or restaurant) that are not in walking distance, how do you hold your campsite or do you give it up? Do you put folding chairs there or is there some other way to mark it as occupied?

Thanks!