Why is it so difficult for major U.S. airlines to be upfront with their customers? Their practices of advertising fares and marketing services remind one of that mysterious “Twin Peaks” revelation, “The owls are not what they seem.”

Last month, I wrote about fake “direct” flights — two or more separate flights that are sold as one under the same number, but are operated on different aircraft and sometimes require changing terminals. That often sends unsuspecting passengers running across the airport to catch what they discover is a regular connection. Knowing that “direct” flights are not what they seem helps to avoid unpleasant surprises during a trip. To avoid such surprises before travel, you should also know that airfares, as advertised by the so-called legacy carriers, are not what they seem, either…