Well I believe that filing a FP does indeed constitute "booking out", the only benefit to "booking out" as you have identified is if you are on a local, with no intention to land away. Then yes maybe some kind of "overdue" action could be taken but not if it's A/G?, as I said unless the destination is fully aware of your POB, route & ETA then forget any O/D action being taken as the departure airfield will not be ringing up to ensure you have landed safely.
An archaic requirement that needs removing under "Red Tape".