I may be flamed heavily for this, but...
I see any moving around the cabin after boarding as doing each other a favor. The other person may have a good-sounding reason to want to change seats, but so do you (the bulk head gives you less leg room and you may want/have to sleep to be prepared for a meeting at your arrival. It all depends. I can't see that anyone has an obligation to switch seats.
With that said, I would not have changed under the circumstances.
/Pete
(those spelling errors again)
[This message has been edited by L-1011 (edited 08-16-2000).]