I've been to several campgrounds where the host/owner/etc. told me to go against the one way sign to get to my campsite. Usually for a valid reason. Either as the OP mentioned, easier, or in some cases, going the "correct" way ends up with my trailer door facing the wrong side on a pull through site. Or a few sites where the pad angle was virtually impossible going the "correct" direction.
IMHO as long as your carefull and there is a valid reason, I have no objection to someone going the wrong way.
And twice I was instructed by the mgmt at forest service campground and once a state park to go the wrong way with my trailer setup and the site I was to go to.
