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I am planning (doing it from France) to fly from PHX to OAK with American Airlines (I am open to any other airlines, that one
seems to be the typical one was readily suggested on that route, but I see there is also SW).
What surprises me is that at no stage of the reservation I am offered to add check-in luggage. There is a "check-in luggage" link, but it just opens a separate page which lists the prices.
How does this work? Should I make the reservation and then, at the airport, go to (check-in? AA booth?) and get the luggage added there?