I know of an off-road only Samurai that is run on Super Swampers wrapped around beadlocks without valve stem cores.
I can't imagine needing them on a camper either. Most that I know with them have leaking issues. Long term the tires just won't hold pressure. Some it's a matter months, others its a matter of days.
I see the legality issue mentioned frequently. I've no idea one way or the other. I suspect that it's a matter of DOT certification, that meeting those stds. may be tough to do or expensive to do. The DOT doesn't test or certify anything themselves. They require any mfg. who wants to claim DOT compliance to submit their product(s) to independent testing to show that they comply, and then maintain the Quality records that show that all subsequent products have been made to the same high standards. For a racing/off-road wheel mfg that's just a bunch of unnecessary BS paperwork for no real gain.
That said, the average LEO isn't going to know the difference, or care.