E.G. Coffee wasn't a European thing in the old world before trade throughout the Middle-East, the Americas and Asia.
Likewise we have no idea what new discoveries we can observe from afar (I mean relative to our own dinky little mud-ball floating in space) than in our back yard of the solar system. So you shotgun the science in hopes of hitting something everywhere.
Who knows if it'll happen in my lifetime, but I'm pretty pumped about it :)
Not especially - developed countries have had declining birth rates for a while now, with several below the replacement rate.
Plus you have to consider that both Antarctica and the Sahara Desert are more habitable than any known extraterrestrial location, yet hardly anyone is living in either.
WHat's the incentive to live there where there are better places to live, still available ?