I've been doing the Gun for Hire thing this past year and I really love it. No band politics or drama to worry about, I just show up, play and get paid.
Ironically, my mental attitude toward the music is different now. You wanna hear Lady GaGa? Sure, pay me. Justin Bieber? ok, whatever, pay me, Mustang Sally? Yup I'll love that song for 5 minutes, no problem, cash only please.
I've placed a premium on the entertainment factor and as a paid side man, I provide a service to the bands that I work with. It's a great relief actually.
I now gladly play songs that I used to hate and refuse to play.
That being said, if I were to join a band again, hump gear, attend countless unpaid rehearsals, put up with passive-aggressive bandmates, compromise my song selection integrity and deal with the same players for a LONG period of time,
I would expect some veto power over the song selection.