This is the much-hyped million dollar ticket fraud scheme that some of the Southwest ticket counter employees at ELP had going...until they were caught in 2003.
They basically pocketed the cash from last-minute walk up ticket sales. However, the customer didn't know the difference (they were able to board the flight). I'm not sure what the intricacies of this fraud scheme were...
Wow, it appears to be a federal indictment! (the US Attorney's office is involved).