The claim is always made that if Americans have to do the work, food prices will skyrocket, but it's just not true. Labor is a portion of the wholescale cost of food, which is a portion of the retail cost. A lot goes to shipping, packaging, processing, marketing, etc. If all migrant workers were replaced by Americans being paid a competitive wage, food prices would go up a little, but you wouldn't pay double for apples, let alone several times more. Highly-processed foods like cereal and pasta wouldn't change noticeably.