Might want to dig a little deeper. I don't have my book handy but I believe all outlets in an RV park have to be GFI. That may carry over to a residence. I know I put a GFI on my personal 50 amp RV outlet without even thinking about it. Considering how bad RVs are wired in general, its cheap protection. See my pictures titled 'Vintage Motorhome' for a typical RV wiring job.
