"Shake Shack Offers Free Antibiotic-Free Chicken Sandwiches Every Sunday, Shades Chick-fil-A"

Shake Shack is offering free chicken sandwiches on Sundays in April, seemingly taking a dig at Chick-fil-A's closed-on-Sunday policy and recent decision to shift away from antibiotic-free chicken. The promotion highlights Shake Shack's antibiotic-free chicken and requires a $10 minimum order using the code CHICKENSUNDAY. Chick-fil-A cited supply concerns for their switch from antibiotic-free chicken, while Shake Shack is emphasizing their commitment to antibiotic-free chicken with this promotion.