I have one on my 30 yo RV. No campground has ever looked at it and we've been full-timing since 2006. My pop-up had one as well. Had it for over 15 years and no one ever looked at the RVIA emblem either. If you think that you will be able to stick one on and get into a campground like Trailer Village RV Park
(see rule #7). Get real. You don't think they will be able to tell that you have a "homemade" RV? As for insurance... they have lists and even if you get full coverage, they won't pay off.