There's plenty of people who live here who have RVs, so you can definitely get around just fine apart from McDonald's drive-throughs and such. I guess the Brew Thru is probably off-limits too
All the NPS run campgrounds (Oregon Inlet, Cape Point, Ocracoke, Frisco) can accomodate RVs, though you have to reserve a spot at Ocracoke half a year in advance.
Here's the info on NPS campsites:
Cape Hatteras National Seashore - Campgrounds (U.S. National Park Service)
If you're traveling further south past the Outer Banks you'll need to take either the Ocracoke-Swan Quarter or the Ocracoke-Cedar Island ferry, which you'll need to reserve a spot for.
Here's the site for ferries, with schedule and reservation info:
NCDOT: Ferry Division