I've never had anyone walk through my campsite. Even when I had a primo spot just above a small beach and watering hole, other campers walked around the edge of my site to get to the beach and water.
I don't see it as being a difficult thing to walk around a campsite. My logic is that if I can't take an extra 20-50 steps to walk around, then I'm not in any shape to be out and about. Even in a rush to the restroom, I will walk around your site.
I do think there are Social Campers, Private Campers and Recluse Campers:
Social Campers - they enjoy visiting with other campers; they will greet you as you walk by; if someone walks through their campsite, they see it as an opportunity to meet someone new.
Private Campers - they will return your greeting; they will be polite if you want to visit, but will limit the conversation to a minimum; they don't want to be your best friend or entertain your kids/pets.
Recluse Campers - they will likely quietly slip by you without acknowledgement; they will stop a visit before it starts; they just want to be alone.
Camping etiquette is knowing that the other 2 types exist (whichever 2 they are) and they have just as much right to their preferences as you do to yours. If you're a social camper and run into a recluse camper, be considerate and let them be. If you're a recluse camper and run into a social camper, be considerate and politely make your request for solitude.