True, if we sent them up there the Martians would probably think we are all like that, then invade us and kill us all. With our only weapon in mars that can be enough to torture. We'd be doomed.
Yeah, it's just a few hundred million kilometers away, with a hostile atmosphere and dangerous radiation all the time. And it's not quite undiscovered, they know they're heading into the middle of ****ing nowhere for the rest of their life.
Yes the environment is hostile, yes they'll have to take immense measures on the simplest things, and yes they're going into the middle of nowhere. That being said, it's still better than going into the middle of nowhere and having to deal with hostile humans.