Disgruntled customers have filed a proposed class action lawsuit accusing wholesale retailer Costco of falsely advertising that its rotisserie chicken contains “no preservatives.” Filed on Jan. 22 in the U.S. District Court for the Southern District of California, the complaint, obtained by USA TODAY, alleges that Costco’s Kirkland Signature Seasoned Rotisserie Chicken contains two added preservatives, sodium phosphate and carrageenan. The proposed class alleges that Costco “has systemically cheated cust ...