Originally Posted by shawbridge

There are probably a few types of transgressions. The first is an honest mistake. Just read the boarding pass wrong. I have done this. The second is a pre-emptive attempt to make a like-kind switch. The third is an attempt to use the norms of politeness to extort a non-like-kind switch. I strongly prefer aisle seats and hate bulkhead seats (I'm tall and my former athlete's knees like extra room. On a flight to Miami, a man is seated in my seat (3B, say). He say, "I'd like to sit with my wife. Can you take my seat?" I say, "Which one?" He says, "1A." So, window bulkhead. I say, "I'm sorry but I choose aisle seats for a reason and want to stick with my original seat." He starts snarling at me. "It is only 3 or 4 hours. ... What can't you switch?" this was an attempt at extorting a seat change -- I'd back down to avoid continuing to assert myself. I think as his unhappiness escalated, he actually swore at me. I politely stood my ground. He moved, though he turned back regularly during the flight and glared at me. His wife was a) apologetic; and b) quite nice.

I think it is this third category of people who try to extort your seat by taking advantage of the norms of politeness that makes people anxious.

Incidentally, someone asked why I said "I'm sorry" or "I apologize." By that, I am saying, I'm sorry that I can't accommodate your wishes. In fact, I'd be happy to do so if they weren't offering me a lesser seat. All other things equal, I'd be happy to accommodate their wishes.

west49th, people are usually especially accommodating when sitting next to kids as they'd rather not be babysitter or handle spills, etc..