Think about this: NASA currently spends billions of dollars each year on conducting scientific research on how living in microgravity effects biological organisms. The International Space Station has cost around $150 billion dollars to build and maintain, so far.
But do we even need to conduct these microgravity experiments? Is that a worthwhile endeavor? I don't think so. And I'll explain why.
Imagine, if you will, a long-term goal for humanity to achieve with regards to space exploration and colonization. What do we want our far, far future to one day look like? There are a few different camps here.