RIAT make a lot of use of RAF Cosford staff: Permanent staff & students who get joed with two airshows in as many weeks.
ATC Cadets have their limitations and cannot be expected to be the voice of the organiser when faced with an irate car driver who whilst trying to get off-site has not moved in an hour. Equally the new-age familes who set up a squatters campsite on the crowdline are a bit much for a young person to deal with. I dont wish to undermine the Cadets; they do a first class job, but quite understandably, only when the going is good. Phase one students and UAS students are little better placed, but thankfully there is usually a gorrilla with chevrons nearby to advise the public on site etiquette.
I did car park management at Finningley once as said 'gorrilla' and created a naughty square (cul-de-sac) in which certain drivers were directed; it guaranteed a marshall manafactured delay and kept team spirits high. The marshallers of all ranks and organisations get more than their fair share of abuse from the tossers in our society.