I'm suspicious about the farmers markets. I'm not saying they all do this, but what is there to prevent someone from going to costco, buying 6 racks of strawber

I'm suspicious about the farmers markets. I'm not saying they all do this, but what is there to prevent someone from going to costco, buying 6 racks of strawberries, then going to a farmers market and selling them at a steep markup? If there's money to be made, people will absolutely do it. And cognitive bias will definitely lead people to claim that "those farmers market strawberries are so much better than the ones from the store..."