I’ve been flying a lot in the past couple of months. Luckily, I tolerate it pretty well. I’m short enough to have plenty of leg room and I can sleep just fine. My pet peeve about flying has turned out to be overhead bin space. I hate checking luggage, so I fly with a carry-on suitcase and a backpack. I dutifully put the latter under the seat in front of me.

However, many people do not appear to exhibit altruism toward total strangers. On many of the flights, the attendants announced that the overhead bins would likely fill up and asked people to refrain from putting their second item and jackets up there until everyone has boarded. I can confidently declare this to be one of the most violated rules in flying. You would think that if people were generally altruistic toward others, more of them would comply. Even though not putting your jacket in the overhead bin probably helps less than donating money to a good charity, it’s also less costly.
There are two possibilities here: most charitable behavior is warm glow (I doubt there’s warm glow from not putting your jacket in the bin) or people really don’t understand the annoyance of having to check your carry-on. Or I don’t understand the annoyance of having your jacket on your lap.