You can beat this subject up all day and night.... I paid in full for a sight once that ended up I couldn't get there till Saturday as opposed to Friday. When I got there the office told me they were about to give my site to someone else.
Sorry, but if I pay for one, two or three sites there mine unless otherwise stated in their rules or explained to me when I make my reservations. Too one of the above posters..... Yes, if you rent the whole park for the whole weekend it's yours whether you show or not.
Unless stated in the rules it's a pretty simple concept.