I've noticed that some FL state parks are tagged as reserves. If so they have split rail fence around the site so that your rear overhang can not extend the useful length of the site. Length becomes a serious issue on those sites. I think Clinch riverside is one of those.
However I've called FL parks questioning how all the sites can be 30' and the person on duty has told me that they can handle much longer RVs and have given me the site numbers with the longer lengths.
I would say that the toss out issue is a result of a cranky gate person and not some "rule" not to be broken. They are always friendly to us, but then we are always polite and friendly to them.