I don’t know if it still applies but I remember being able to buy day membership to the PFA to get airside at the PFA Rally. I know it is the LAA now but I haven’t visited for a good few years.
I also remember having fairly harsh words at one of them with a “gent” with his very young son who wandered up to a Tiger Moth and began to try swinging the prop even though he had nothing to do with the aeroplane.
He initially told me to mind my own business but having explained the possible danger to himself and others he just swore at me and walked away. – nice man!