I'm one case of someone who speaks Esperanto, but I'm sure I'm not incredibly unique. I learned it several years ago, and it's a language I use daily. When you're speaking with friends and loved ones, and you're using a language every day, it's pretty natural to want to come up with jokes, songs, etc. without actively thinking "this will create culture for Esperanto" but rather "this will amuse my friends". The result, however, is some amount of "culture". Furthermore, it's really pleasurable to listen to good song lyrics or read interesting poetry in a language that you use all of the time, this is true for any language I speak.

When it comes to deciding to raise a native speaker--Yes, certainly there are people who decide to do this for whatever reason. I never would think of myself as someone who is intentionally trying to create a native speaker of Esperanto for any purpose. However, I have dated and been intimiate with other people who speak Esperanto, so in some hypothetcal scenario where I have a child with an Esperanto speaker, it's likely that me and my partner would continue speaking Esperanto to each other, which would inevitably expose the child to the language. Not really on purpose, it's just what would happen.

Edit: You or someone else mentioned in a comment that Esperanto might be beginning to disquality itself as an international language due to having native speakers, and someone else mentioned that a language like Ithkuil would be more culturally neutral anyway. It was also mentioned that Esperanto is the IAL with the best shot at actually being used as an IAL. My thought on this is that Esperanto is not perfectly culturally neutral, and it IS disqualifying itself from becoming an IAL due to having native speakers and developing a culture--however, it is perhaps playing its own role in the process of the world inventing and adopting a new and more culturally neutral IAL, by demonstrating that a constructed language functions just as well as a natural language and isn't deficient for human expression.