I once did a boot sale as a teenager with an elderly and rather eccentric family friend. We'd been to them as buyers with him and we came up with idea of doing our own, so we gathered together the stuff that we wanted to sell and loaded it into his car (my family didn't have a car).
He'd been very keen to do the boot sale, but he hardly had anything of his own to sell - just a few bits of random rubbish (think bits of used old car parts to fit some random 25yo model). I think he just fancied a day* out. He'd brought his flask of coffee and sandwiches (fine) and his beloved accordion, which he played very loudly, incessantly, repetitively and not completely tunefully. It was a nice one (by far the only decent thing in among all of his tat) and plenty of people made him offers to buy it. At the time, I wondered if people might be trying to take advantage of a dotty old man and buy quite a valuable instrument from him for next to nothing, but looking back now, I wonder if their intentions were mainly humanitarian ones, to diplomatically stop him from his breach of the peace.
He'd brought a huge box of home-made cassettes - recorded from the radio and labelled in scrawly biro. He wasn't trying to pull a swifty one, he was just not very worldly-wise and it had honestly never occurred to him that it might not be legal to be an 'accidental pirate'. I gently tried to steer him away from putting them out for sale, but he genuinely didn't get what the problem was as 'but some of these are quite rare and people might want to buy them' nobody did.
It wasn't in a field, but the largish but quite confined car park of a local council building. I can't remember if it was our decision or the only space left by then, but we ended up in the very far corner from the entrance. He cheerfully drove on through, parked up and we unloaded.
After about an *hour, with the place absolutely packed with stalls and buyers, he announced out of the blue that he needed to take his wife shopping. They were a retired couple and could have done their shopping at absolutely any time, but it was somehow essential that they do it right now. The commotion that it caused (he wasn't that great a driver, which didn't help), with everybody having to move their tables out of the way and a heaving car park full of people who had to all crush in to the sides to let him come by. I was soooooo embarrassed.
However, by the end of it we were resolutely only the second most embarrassed people there. The outright winner was another stall-holder who decided to be the first to leave as things were really tailing off but before the event had properly finished. They were an even worse driver than my friend and were making a bit of a slow-motion Austin Powers of it.
There was a very large stall right near the entrance - a regular seller specialising in all manner of decorative plates, glassware, crockery and a great many other similar breakables, all arranged in tiers on numerous lengths of wood on upturned buckets. You can probably guess what happened next and the ensuing furious row about whose fault it was - bad driver or precarious displayer. I'm guessing that at least one if not both stall-holders ended up making quite a loss on that one 