Traders are not angels, there is a measure of anarchy inherent in the process. But there are ways of guarding against the grabbers, it does take organisers' time though. My original motivation for the thread was to voice disquiet on behalf of traders who probably feel inhibited here. And to add my preferrence to the mix, with pointing fingers.

One event ticket per stall would control it somewhat. Presumeably traders would have trader passes to get on site that would not be acceptable on event doors.

You do hear comments from punters - "it is the same tat everywhere" but they are expressing personal taste, one man's tat is a kiddies plaything. I usually browse the alledged tat and that is entertaining in itself, to a degree, call me sad.
I do buy wine from Granny West, and would be sipping it now if I could get the cork out. Cheers