I'd bet that almost every rule on those signs are a matter of common sense. I'd also bet that the sign exists because some campers don't have any common sense.
"Please don't slam the lid on the dumpster" "Please don't bring glass containers into the pool area" "Please observe the 5MPH speed limit" "Please walk your dogs in the signed area" "Please use the fire ring for campfires". "No adults on the children's playground equipment".
I must admit, though, that when I'm feeling frisky, I sometimes drive 7 MPH. Don't tell on me. :)
