The universe is unendingly gorgeous, but we seem to have decided the only way to portray that is with SATURATED colors that are VIVIDLY in your FACE.
Reality can be much more subtle, and as a result, far more beautiful. Sometimes, it takes watercolors to remind us of that! The often fantastical nature of space opera stories lend themselves to it quite nicely as well, so bam.
Art by http://annakrupa.deviantart.com/gallery/