For Delta Airlines, the answer is completely withdrawing its data about flights, tickets and pricing from several third-party booking sites. Furthermore, without comparison prices alongside, customers won’t know whether they are getting ripped off. Nowonline agencies are beginning to fight back against what they see is an unfair practice by Delta and other airlines. In a report by Travel Technology Association (Travel Tech), several travel websites — including TripAdvisor, CheapOair, and Hipmunk — have banded together to voice their complaints against the policy, and Travel Tech has sent a copy to the Department of Transportation for review. Destinations, also unhappy with Delta’s decision, are rooting for the websites, as they represent a big source of revenue for them.