Change the programming and go back. I wonder what reaction back here would be...

Not really possible for many mission profiles (e.g. if using target system star for braking or pre-programmed beamed propulsion) - so often that would not be an issue. ;-)

Not really. That would just be the way life is to those people. Showing them videos of how people lived on a planet would be like asking them to imagine how a caveman lived.

If they did rebel it would probably be more along the lines of reaching the target inhabitable planet and refusing to leave the ship. Just grab enough material to set a new course for the next one and keep going.

The next set of rebels would be the ones who actually fulfilled the mission.

Living on a ball of rock with no climate controll ? Are you insane ? Do what you want, I'll go back to building that new custom Stanford Torus we just got started last cycle. And don't call for help when it inevitably starts raining!