Pigs is pigs, buddy.
You gotta play along unless you wanna start shit. And pigs being pigs means you can't really start telling them what they're doing is inappropriate or unnecessary, that puts em in fight or flight mode and pigs don't fly.
I'd guess your best bet would be that they get used to you and become nonchalant with their check-ins. Just be stupid friendly about the whole thing and maybe try to remember a few of their names. If it's a small town, can't be too many of em. Eventually maybe you can shift it from "Good afternoon, Officer, what seems to be the problem?" to "Ah hey Steve, Mrs. Granger worried about me again? Aint that sweet, how's the kids?"
Edit: I see elsewhere in the thread you mentioned you're living in the van. That makes things harder. Even if you're complying with the law, pigs hate that shit. When I was living in a car, I had a sob story ready for any cop that interrogated me and if I got caught and had to use it, I wasn't sleeping in that county again for another month. The campground bit is especially fucking frustrating, you PAID to be there, that's all on the up and up. They're monsters, buddy, not sure how to help, but I find being some caricature outta some 50's PSA film to em pads their egos and smooths interactions in general. Tho the shoddy van won't help.