Changing flight dates. . .

Whenever my friend flies JetBlue, he winds up going home a day early or late
and says they only charge him $50. Whenever I call and ask about doing that
they have to reprice and THEN add $50 to that.

Could it be that they waive it if you just show up at the airport on a
standby basis and throw yourself at their mercy?

I was told when in Europe once that my frequent flyer ticket (another
airline completely, NW) could not be changed and I would have to buy another
one-way for $5K, just to come home a day early for a friend's funeral that
died suddenly.

Is this just what they say on the phone to dissuade people, or is it best in
these situations to just go to the airport and pray someone lets you
through? I used to travel all the time, but nowadays not so much.

Any suggestions much appreciated.

thanks
enzosf