In my limited experience, I try to plot out where I can stay while on the road that will cost me the least, so I can devote more of my money to good accommodations at my destinations. To that end, I have pulled into campgrounds and paid for a spot at the last minute when I can't find anything else, but will always try to find a Flying J, Cracker Barrel or Walmart for my nights on the road. Some CB's do not have long enough RV spaces for my rig when I have a toad, but all will try their best to making sure you're happy. They cater to RV'ers and OTR drivers because the chain was originally begun by an OTR driver. I showed one manager how I was hanging over five feet to the front and three feet to the rear and asked if that would be a problem. She said that was nothing compared to some she had seen.
Flying J's can be noisy, depending on where the RV parking is located, and oftentimes, I have found the parking area to be on severe slants which can cause a problem with your refrigerator if left at a steep angle for too long.
I don't believe in setting up camp at a Walmart, CB or FJ and will never bring out the grill or extend the awning, but regardless of where we park, the bedroom slide has to be extended or we won't be able to sleep. Likewise, on the same side of the coach, we will extend the kitchen slide so we can cook, but the slide on the other side of the coach stays in. When possible, we park with the driver's side next to an island so the slides won't be in anyone else's way. That makes it convenient for us to walk our dogs, too.
We will stay only long enough to fix a meal, sleep, fix breakfast, and then hit the road. We will also never leave behind trash and will pick up after our dogs. That way, it will look as though we were never there. The slobs that leave their trash in the parking lot are the ones who spoil it for the rest of us.