Most retailers love gift cards because they get the cash early and a % of people forget they have the gift card==free money. Seems like the airlines would love up-front cash right now given their credit issues.

Not airline related exactly, but I think I read somewhere that Starbucks has over $1 Billion in gift cards outstanding and that they make a significant amount of money on gift cards that aren't spent and also the returns on the cash they have gotten early. That's why you get free upsizes/refills, etc. when you use sbux gift cards at their stores.

(Note: Before someone says that Starbucks is evil and wants people to lose money, they will replace any lost or stolen gift card provided you have registered it online with them, so you can reclaim the value.)