OK...lets say your camper is a 4500 lb monster like a Lance 1191 or an Arctic Fox 1140 or a heavier Eagle Cap 995. You may get off the pavement to camp but you aren't going to do the Whazoo with it. ...
4X4 if you want to be off-pavement at all. I've needed it for at least a few feet of slippery mud or sand or such on nearly every trip. I explore a lot of dirt roads and rarely need 4WD for more than a short distance.