Silvaire1 - you must remember that the UK (i.e. CAA) philosophy for light aircraft is totally different to the USA (i.e. FAA).
I am curious to know, however, if all USA airfields operate the way you suggest.
If I decide to pop across to Atlanta Hartsfield in my Navajo, can I just call up ATC, get a clearance & land ?
How about just landing the aircraft and finding your own parking spot? Stick it in some corner if necessary.
Can I park in an odd corner there so I don't pay ramp fees ?
The 'booking out' by phone thing is just crazy
When I'm ready to leave can I just call the Tower, get a clearance & go ?