I'll never switch seats with you, ever, short of you offering me a business class seat, or cold hard cash, or something material for the inconvenience of packing up all my stuff and moving to a different seat. I had the sense to book my seat ahead of time so I can get a good seat, and I'm not giving that up. And if pushed for a reason, I'll say "I don't want to. That's all."

I always book non-bulkhead window, and with UA's WilMA boarding I'm always on after the Star Golds and Star Silvers and what not (from May I'll be boarding with the star silvers, thank you), and most of the time by the time anyone asks I'd probably be settled into my seat.