Science fiction and fantasy bookshops are a good source of new readers to comics,usually stocking the better or more popular graphic novels if not the regular 'floppies'. It's a natural enough fit; though I don't know whether they've been known to include such titles as Batlash, Sgt Rock of Easy Co, or Korak Son of Tarzan, which reside outside both genres.
At first even the alliance of science fiction with fantasy seems a strange one; one always uses empirical evidence as its starting point, the other uses a different base altogether.
Well, these genres are profoundly affected by linear time - the more humans discover new things about their past and their future, the more an idea is seen as first fanciful, then possible, then probable, and finally concrete and actualised. Any exploration of this idea in a story will be seen in a different light correspondingly; what may start out as fantasy could end up as science fiction (or even science fact), while the reverse could happen where something that seemed plausible when it was first posited now contradicts too greatly what we now know to be true.
Not that writing fantasy allows you to put down the first thing that comes into your head. Fabricating a world, peopling it, making sure there are no inconsistencies within the fabulation, constructing stories that are authentic to the setting but still identifiable to the reader out there 'in the real world', all of this is potentially more work rather than less. You can potentially fudge the details when placing a character or event in a 'real setting' - use your research and some markers to suggest geography and you're away. But write fantasy and you need to understand for yourself what the motivation is for entire tribes and lands. You need to invest them with a language and sociology that makes sense, given the natural environment and the particular threats and challenges they must face.
[this year's quiz is late and over at the general blog]