I cannot understand the logic which leads some people to believe that if my sole carry on is a briefcase and I put it in the overhead, making it difficult for him to fit in his two oversized bags, I am the one who is selfish.

For that matter, I also cannot understand why I am expected to make the flight wearing my heavy winter jacket, and not put it in the overhead, if I have nothing else up there.

(I used to get around the latter by folding it carefully and putting it into my rollerboard. As I have been flying Biz Elite/FC for the past few years, it has no longer been a problem. The FAs hang it up for me.)