Fantasy vs Sci-fi vs Fantasy vs Reality. What?!

Failure or mindset?  Looking back, this is the question I ask myself.  Why was I unable to garner interest in people to 'try' science fiction based role playing?  I think the answer lies in identity.  For some odd reason players I have gamed with have a difficult time connecting with a science fiction driven universe and all its modern trappings. Whereas its opposite number, fantasy, no problem.  Could it be an historical thing?  Or the fact that, as children, we are more often told and read stories firmly rooted within the 'traditional' fantasy setting of witches and fair young maidens, or of dragons and brave knights?  As opposed to battle-suited, laser-blasting troopers versus homicidal space amoeba within the depths of deepest, darkest space?