Until I read this post I'd all but forgotten about flights that I booked for myself and friends a few short years ago, a domestic flights in a developing country on their national "mythical" airline.
The tiniest bit of research showed me that for an extra $US10 each we could move from Y to J for the two hour flight. Three of us chose to shell out the extra, the other three claimed that they didn't see the value in it. They were a family, cried poor and said that it meant $30 for them where it was only $10 each for us (I don't understand the mathematics there, but when people play the "family" card strange things often seem to happen).
We had access to one of the loveliest lounges I've ever come across in what is otherwise a very basic airport, and had a very comfortable flight in a newish plane. Best $10 I've ever spent, and a very cost-effective few minutes worth of research. This wasn't a special deal, it was their standard rate booked over the phone direct with the airline.
Again, my thanks go to those of you, including my thrifty friends, who insist on sitting down the back of the plane thereby freeing up seats at the front for those of us who appreciate the extra comforts.