Originally Posted by
ethernal
Different incentives. Expedia has incentives to find and ticket the cheapest possible fares to customers. Delta has the incentive to maximize revenue from fare sales. It is not surprising that delta.com breaks on fares that - while perhaps are legal tickets - may contradict this objective because they are unintended fare combinations.
These are perfectly normal tickets and fare combinations . It's just that the Delta booking system for the last year I've found is c***py for non-straighy forward tickets.