I fly a fair bit for work, and I have to agree with most of the statements here.
That includes the people stuffing stuff in the overhead. I do carry-on only, but that is because I typically cannot afford to lose anything in my luggage, not because $20 matters. I get quite annoyed when people sitting in the back of the plane put stuff in the front.
When I got sent to California recently I rather rudely ousted some people's baggage from up front for them, so that the people in the first row had somewhere to put theirs. The stewardesses were trying not to laugh while scolding me. :)