Andrew,

Behavior like that would get them banned as vendors from most of the Flea
Markets I know.

This might possibly be a case where "The eBay Effect" was in action.

This has been discussed on OLDTOOLS many times over the years.  It's especially
pernicious because some Flea Market sellers think the prices listed as "Buy It
Now" are indicative of what the item actually sells for.

John Ruth
Metuchen, NJ