Consumers are demanding it, and it's not just a fringe, foodie phenomenon. That's why McDonald's no longer buys chicken that was raised with antibiotics that are also used to treat humans. Panera, Chipotle and Subway don't either. Chick-fil-A, Papa John's, Pizza Hut and Taco Bell have publicly committed to doing the same. Last year, shareholders in KFC warned that the company was likely to "lose market share to companies who have stronger policies in place." Smart businesses give customers what they want. That's why Perdue has led the way, with Tyson Foods and other big producers following its lead.