I'm glad that people like you exist. I hope we have more people with such an adventurous spirit. It's one of the great things about the human race is that there are so many of us, each of who find different things fulfilling. You can do what you love, I can do what I love (staying firmly on earth), both of us are happy and we take humanity forward!
I guess the point I'm trying to make is: having a lot of people is beneficial, because then there is likely to be someone who is happy to do the things that you aren't so excited about.
You are very right - I fully understand why people would want to stay behind! I'm very passionate about this, though, and I tend to get grouchy when people argue against doing it at all. If they don't want to go, that's fine, but when they start arguing that no one should do it, I see them as actively trying to hold back human progress for no good reason.
I guess the point I'm trying to make is: having a lot of people is beneficial, because then there is likely to be someone who is happy to do the things that you aren't so excited about.