The GP said the novelty will wear off in one hour, tops. Sorry, to some people, that's a ridiculous statement. Pointing out that it would probably last longer than that is not insisting that it's going to be one big breathless adventure.
People have lived in solitude and isolation before. People have lived on the space station for extended periods of time. There are people that don't really care to come home to their comfortable home and family every night. I'm pretty sure there are some people who would not be miserable living on Mars.
... wait a minute... DOH!
But I'm sure some people would love to explore places where no human has ever been before for the rest of their lives.
There is also the work of building a new society, settling in new immigrants, improving infrastructure in your settlement etc, that has to be fun for the right kind of person.
So I'm sure that a small percentage of the populations would genuinely like living on Mars. Maybe he biggest problem is predicting who those people are before you ship out :)
This sounds close to the neck beard trope, of people living in their parents basement and never seeing sunlight. Could we inadvertently be adapting to a Martian or Lunar environment?
It will totally be worth lifting 250kg of human adipose tissue into LEO, I swear. If the food supply fails, you'll need someone that can survive without it until the next available harvest. Not that I weigh that much now, but with some intensively sedentary neckbearding, I can probably get that high by the time we're ready to launch.
A better analogy than backpacking would be permanently living underwater at great depth. To leave your underwater habitat, you have to scuba dive or get into a submarine. You never get an unmediated experience of the outside world. Your skin touches the inside of your suit. You smell only the air from your breathing apparatus and your own breath. Forever.
I'd be way more impressed with Mars enthusiasts if they'd admit that this is a problem and then describe how they'll overcome it, rather than just insisting that it all really is going to be one big breathless adventure. It's like mentioning boredom on Mars is a taboo that upsets frail escapists.