COLUMBIA, S.C. — The flap over an ad promoting South Carolina as “So Gay†will cost the state tourism dollars, according to an industry expert. Gay and lesbian travelers will likely be turned off by the political posturing surrounding the ads, which were pulled by the state tourism agency and led one employee to resign. “We experience discrimination every day, so we certainly don't want to when we travel,†said Wesley Combs of the Washington-based communication firm Witeck-Combs, which specializes in gay, lesbian, bisexual and transgender travel. Combs noted that national media attention about the ad, including jokes on Conan...