Some airlines ask to see the credit card used to pay the ticket or they won't let her board. Better to inquire about it; if this is the case, usually you can circunvent it going to a bricks and mortar point-of-sale for the airline, present the card there and ask for it to be annotated in the PNR.
At least within Europe, I've never encountered this unless you choose to set the credit card as the "identification method" at check in.
Originally Posted by
Gamecock
I lived in Germany for 6 years and somehow was able to buy tix via the AA web site and pay in dollars at a cheaper rate.
Now that I am back in the US I buy tickets for German family to come visit. Not sure if I was/am violating any T&Cs.
I've had it happen where it's just a few dollars based on difference in what exchange rate the airlines are using, but on occasion the differences are in the tens of dollars.