That very vocal trader, at our local show was told by the organising club to pipe down or get out.
Whilst I’m not against under the table trading, I’ve done it myself. Three things really annoy me.
People who can be seen at every show selling from under the table. They are obviously running a business but too mean to pay for a traders spot.
Modellers that walk down the rows of tables looking underneath them and not at the models. Personally I make two circuits, one to look under the tables and one to look at the models.
Traders and modellers who pester you to look at under the table sales before you have finished setting up.
I like Telford’s approach with the kit swap, which I have never visited. However this is a big undertaking for most club run shows.