At Wycombe Air Park (Booker) we don't have to wear hi-viz jackets despite having one of the busiest 'airside' GA operating areas in the country. It works fine without anyone getting run over, people are just sensible!
A friend of mine landed at Norwich, went through to meet his passenger then wasn't allowed back airside by the security man to his plane because he didn't have a hi-viz jacket.
'How do you know I haven't got one?' he said.
'Because I saw you when you walked in from your plane' came the reply.
'Well if you could see me, I obviously don't need one then do I?'
Conversation ended with a quietened security guard.....