I have no specific knowledge in this area, but I do have an opinion, fwiw. If you're talking about passive selling to fellow campers who are out walking their dog and express an interest, I doubt anyone would take issue. Unfortunately, I also doubt you'll make much money. If you're talking about active selling, advertising, and using your RV as a storefront, I think a great number of people will take issue, mainly because you're bringing additional traffic into the area and people who are not registered and really have no business being there. I certainly don't want to be camped next to you under those circumstances.
My suggestion would be that, if possible, you consider selling your product at festivals, fairs, etc., and using your rv to engage in that business approach. Lots of people do that, and it affords you the opportunity to go where you want, when you want. My $.02, probably worth less than that.! Good luck in your endeavors; it sounds like a nice product. And welcome to the forum!
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โCertainly, travel is more than the seeing of sights; it is a change that goes on, deep and permanent, in the ideas of living." Miriam Beard