Fwiw, there are a lot of highly frugal people in eg the surfer/kiting community (example!) which do indeed spend pretty much nothing where they're visiting for their hobby.

And they do often smell and leave trash behind.

So I can imagine that being true if you're living in one of those hotspots... It's a hard topic though

Let me set this straight: My point is you have an incorrect idea of how much space a month of food (and it needn't all be rice; that just illustrates the point) takes up. You can readily fit it in an RV, especially a big one.