Ticket most likely wasn't bought that way. To buy multiple tickets to cover what can be bought as one usually costs significantly more than buying a single ticket. I read the entire thread and I'm sure it was posted upthread in the original post, how it was purchased, but I'm going to bed and too tired to read it over again.

And our manager sends out a spreadsheet to us of all the fines we have gotten for invalid immigration documents as well as the number of time we as a gateway city have stopped someone who was supposed to have been verified upon initial checkin and refused them boarding for improper docs that were not caught at the initial point (both are process failures, the 1st result in fines, the 2nd result in fines saved by a addl check at the gateway flight.)