Originally Posted by Fly AA J all the way

You aren't stealing, they are. You are pulling out cash and asking for a better seat. No telling what they are typing into the computer, but if they accept, you are paying what they told you the upgrade cost. If they keep the money, it's stealing, but it's them stealing from their employer, not you from the airline. I see no problem with it, and if I were smooth enough, I'd try this as well.