Seems to me that most of the panic is completely valid in that it affects folks trying to book tickets for a group of family/friends who normally sit together for League games. FAC online booking process for such an arrangement appears to be distinctly tricky. Strongly suspect if you didn't have...
You'll get an email (eventually) with a PDF attachment. You print off the PDF attachment. The PDF attachment has a barcode on. As others have recommended, set your printer to maximum quality before printing and also maybe stick it on your phone as a Plan B.