Growing up, we had thousands of books in the house, and a LOT of them were science fiction or fantasy, so that's what I ended up reading. They were more interesting than a lot of other genres to me. And when we had a working television, which wasn't often, we watched ST:TOS. Over and over again. And when we saw movies at the theatre - which wasn't very often as there weren't any in a lot of the places we lived - inevitably the parents took us to see science fiction/fantasy. As my sibs (I'm the youngest) contributed to the book collection, inevitably, they added more science fiction/fantasy than other genres. So, you know, it was inevitable.
