Latest blog post: End of the chapter 5, and a short hiatus (2024-02-19)
So it goes
What could they possibly take from us that they couldn't get more easily elsewhere? Raw materials they could mine in any system. Habitable planets that never developed multicellular life and are open to colonization are surely far more common that habitable planets with inhabitants that'll fight back. Slave labor is unlikely to be economically viable in a society that has a decent grasp of automation (unless of course having inefficient slaves is a status symbol). Cultural products are difficult to cultivate in captivity.
Eh, it depends on technology. Oxygen is plentiful in the universe and not that difficult to extract from compounds if energy is available (and for a spacefaring culture, it is). Same goes for almost any mineral resource.
Now, a planet with a complete working biosphere that can be studied and/or settled... THAT is a treasure trove.
lots of carbon dioxide on venus in atmosphere and enough nitrogen (3.5%) to easily extract. Moon titan, absurdly large amounts of nitrogen, methane and water. So places other than earth as sources, though may take more processing to get rid of radioactive isotopes.
comets are full of ice, and may have lots of nitrogen as ammonium salts, no big gravity well to get out of.
Meh, it shouldn't be that hard - why do humans explore the Marianas Trench? *Because they can*.
That's what "true explorers" do. That's what scientists do.
Of course, there are those who do explore for *other* reasons - the question is blunt, distrustful, poorly worded.... but not truly unwarranted.
It's also worth noting that stumbling upon a sapient world is ridiculous luck (alliance had surveyed something short of a million star systems, found only 15 extant civilizations, so the actual chance of stumbling upon somebody new is roughly 0.000015%). They could easily select Tau Ceti instead of Sol as the jump target, and then not only the plot of the comic wouldn't happen, Earth could remain undetected for further thousands of years.
Edit: It can even be considered pretty much canon fact that there's undiscovered sapient civilizations within the Alliance territory.