It may be easy "enough" but I don't know that's "very easy". I don't know of any way to set up the online accounts at any of the airlines that I have to automatically always book my trips in Person X's name. It's set up to always book my trips in my name, to record my security information, etc. Everyone else I have to enter from scratch each time.

So at the very least it's a bit more hassle to book flights for someone else than for yourself. I'm not saying it can't be overcome, but I'd be annoyed if every one of the flights that I book, including sometimes multiple MRs booked in the course of minutes, I had to keep entereing that info over and over and over agian, just because I'd intentionally made it wrong once year ago in an effort to scam the airline. (It's one thing to ask the ailrine to change your name because you got married, it's another thing to ask the airline to change your name because you're done scamming them for a while!)