Most likely the manager was getting his hiney chewed. He probably broke with policy and held a site for you without getting a deposit. Might even have had to turn away a guest or two that night and then the site went unused. Maybe the person in charge of the park was checking the records and asked why they were turning away guests when the park wasn't full. Maybe one of the people turned away for that site he held for you was someone in city government and when they found the site went unused they started asking questions.
There are probably multiple checks and balances in place to prevent an assortment of things. A site showing reserved that suddenly goes unfilled could mean the manager is skimming off cash. It could mean that the park is not fully utilizing it's sites, hence not maximizing it's income. Even though it is a municipal park, that revenue is still important.
