At a swap meet, hobbiest/vendors can rent a sales table for $25 and sell fish,plants, equipment, etc. for whatever price they want and keep all of the money. The public is charged $3 to get in with discounts for families. This tends to bring out more high end goods that someone wouldn't want to risk selling at auction.
Hours will be from 11-3 so if you are buying, you can spend as little or as much time at the meet as you like and still have a chance to buy everything you want.
I know there will be lots of plants at this meet. It will also be open to freshwater and saltwater sellers.