Trying to book a roundtrip flight from Houston to Chattanooga in June. Looks like Delta and American Airlines are the major carriers. I don't like flying Southwest Airlines. I like booking flights directly with the airlines. So far,booking a flight through Expedia is way cheaper than booking direct with AA or Delta. That's the first time that has happened to me trying to book a flight in a long time. It's got me wondering why it is so much cheaper with Expedia. Anyone had a similar experience recently?