There may be someone who try to bid you out, keeps eyes on bids. It can be a bid for all the vendors to get first "free" one or one only on your stand. If only on your stand, someone may dislike your prices, like the lokation of your stall or dislike you and try to shut down your stall.
As there are free stalls at the moment, it seem like someone are going for your stall.
It's not a nice thing to do as it's very sad to see your stall gone.